Shudder TSB 18-NA-355 has been updated 7/19. I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done.The auto manufacturers had no legal obligation to repair the cars. Technical Service Bulletins are issued by manufacturers when there is a problem found in a number of cars which does not have an ...Page 2 March, 2019 Bulletin No.: 18-NA-355 Shudder Test Refer to the table below for conditions pertaining to specific applications. In each vehicle, constant throttle input on a smooth grade is desirable. PicoScope Measured Frequency is the approximate vibration frequency where TCC Shudder can be found, discussed in detail below.The auto manufacturers had no legal obligation to repair the cars. Technical Service Bulletins are issued by manufacturers when there is a problem found in a number of cars which does not have an ...Oct 4, 2017 · TSB 18-NA-355. Note: Required tool kit DT-52263 is shipping from Bosch. All DT-52263 tool kits will ship from Bosch no later than February 14, 2019. If you encounter a vehicle with Torque Converter Clutch (TCC) Shudder prior to receiving tool kit DT-52263 please postpone the repair until you receive your tool kit. Performing repairs other May 6, 2022 · The issue about the TCC shudder that many of us have experienced, and apparently carried over to a variety of GM models with the same trans assembly, seems to pretty accurately described in TSB #18-NA-355 (22 pages). I got the TSB number, because the dealer printed it in my service invoice (N/C, since I am under the powertrain warranty). Apr 21, 2023 · This problem currently affects 11 different models across 3 different OEM brands for the model years between 2015 and 2019. After implementing several fluid revisions, GM’s latest solution (TSB 18-NA-355) is lengthy, complicated and expensive. It If your car is a 2018, it has the A8 and not the A10. The latest transmission fluid (Mobil 1 Synthetic LV ATF HP, part number 19417577, blue stripe on the bottle and not black) that actually fixes the problem came out in Jan 2019 as part of TSB 18-NA-355, so unless your A8 was flushed with this specific fluid, it can develop the shudder. General Motors (GM) has been ordered to pay more than $100 million to classes of vehicle owners who argue the company sold vehicles with defective engines. A federal jury in California delivered the verdict against GM after less than one day of deliberation. It will benefit three classes of around 38,000 GM vehicle owners from California, North ...Sep 18, 2019 · C7 General Discussion - LATEST TSB 18-NA-355 for AUTO TRANS SHUDDER - I found and attached the latest TSB 18-NA-355 regarding automatic transmission shudder. It was on the NHTSA website. The latest update is July 29, 2019. I also found another bulletin that applies, see attached TSB 19-NA-142 CAUSE Road test has shudder when the torque converter is applied. Command TCC on and shudder goes away. Checked fluid level and found condition is full and in good condition. Checked bulletins found #18-NA-355 said to flush and drain fluids in the transmission. CORRECTION Flush and drain fluids for transmission shake/shudder repair.Drives: 2018 2SS. Join Date: Aug 2017. Location: Western PA. Posts: 133. July Update #18-NA-355. Anyone have a copy or link to the most recent shudder TSB? Looks like no diagnosis required if built before March 2019 based on the July update. Only customer complaint needed for dealers to perform the flush. I think I may have the start of the ...Mexico and Export Regions should follow Bulletin 19-NA-018. Note: This procedure should only be completed once per vehicle. Any vehicle that returns with suspect shudder should be diagnosed utilizing published diagnostics, GDS, PICO Scope or other diagnostic tools. Sometimes shudder is not caused by the torque converter clutch (TCC).TSB 18-NA-355. Note: Required tool kit DT-52263 is shipping from Bosch. All DT-52263 tool kits will ship from Bosch no later than February 14, 2019. If you encounter a vehicle with Torque Converter Clutch (TCC) Shudder prior to receiving tool kit DT-52263 please postpone the repair until you receive your tool kit. Performing repairs otherJul 29, 2019 · Shudder TSB 18-NA-355 has been updated 7/19. I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done. This video is just a walk through of what you might be dealing with if you feel an unusual shudder.Subject: Shake and/or Shudder During Light Throttle Acce...Jul 28, 2019 · Evidently that one and 18-NA-355 have just been updated with the new information and keep their #s. 2017 GMC Canyon Denali V6 CCSB 4X4 [/QUOTE The TBS # on the work order for my 2019 Colorado was 18-NA-355. 20 qts triple flush 7/29/2019 TSB 18-NA-355 is the one you want, but it also states to not replace the torque converter. With that said I was able to get mine replaced with the fluid/flush. It's likely dealer dependant. In my case the dealer saw the metal shavings in the fluid from the torque converter clutches, so they told GM, and they said to go ahead and replace itJul 29, 2019 · Shudder TSB 18-NA-355 has been updated 7/19. I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done. Apr 21, 2023 · This problem currently affects 11 different models across 3 different OEM brands for the model years between 2015 and 2019. After implementing several fluid revisions, GM’s latest solution (TSB 18-NA-355) is lengthy, complicated and expensive. It Had New TSB #18-NA-355 (A8 Shudder) Done. FYI, if paying out of pocket for this it is 3 hours of labor versus the 1.6 in the bulletin. It took every bit of those 3 hours. I watched. GM evidently doesn’t reimburse dealers for full labor time on warranty work; hence the 1.6 hrs in the bulletin vs 3 if paying out of pocket.Title: #18-NA-355 - Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40 and 128 KM/H) at Steady Speed - (Mar 30, 2020) Vehicle: 2017 Cadillac ATS The document preview is shown on the right. To view the entire document you need to have a subscription. Subscribe #18-NA-355 - Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40 and 128 KM/H) at Steady Speed - (Mar 30, 2020). Service Bulletins - Service manuals, electrical schematics and bulletins for 1995 to current GM vehicles. Chevrolet TSB 18-NA-355 Make: Chevrolet Number: 18-NA-355 Title: Shake And/Or Shudder During Light Throttle Acceleration Between 25 And 80 Mph (40 And 128 Km/H) At Steady Speed Date: 1/17/2019 Models: 2017-2019 Camaro LS; 2016-2019 Camaro LT; 2016-2019 Camaro SS; 2017-2019 Camaro ZL1; 2017-2019 Colorado; 2017-2019 Colorado LT; 2017-2019 ...The issue about the TCC shudder that many of us have experienced, and apparently carried over to a variety of GM models with the same trans assembly, seems to pretty accurately described in TSB #18-NA-355 (22 pages). I got the TSB number, because the dealer printed it in my service invoice (N/C, since I am under the powertrain warranty).Jun 5, 2018 · Chevrolet TSB 18-NA-177. Some customers may comment on any of the following conditions: A shake and/or shudder during light throttle acceleration between 25 and 80 mph (40 and 128 km/h) steady state driving when transmission is not actively shifting gears. A shudder feeling that may be described as driving over rumble strips or rough pavement. GMC TSB 18-NA-355 Make: GMC Number: 18-NA-355 Title: Shake And/Or Shudder During Light Throttle Acceleration Between 25 And 80 Mph (40 And 128 Km/H) At Steady Speed Date: 1/17/2019 Models: 2017-2019Canyon 2018-2019Canyon All Terrain 2017-2019Canyon Denali 2017-2019Canyon SL 2017-2019Canyon SLE 2017-2019Canyon SLT 2015-2018Sierra 1500GM issued a Technical Service Bulletin TSB 18-NA-355, with updates that address the “torque converter clutch (TCC) shudder conditions.” The problem was identified by many customers who reported the transmission shuddering frequently and shifting harshly between first and second gear.Jan 4, 2022 · They were not willing to admit that this is a widespread problem. I showed them the TSB 18-NA-355 that describes the problem. They said a new TSB was released in 2022, TSB 16-NA-361, where it states that this is normal operation and replacing any transmission components will not resolve the problem. TSB 18-NA-355. Note: Required tool kit DT-52263 is shipping from Bosch. All DT-52263 tool kits will ship from Bosch no later than February 14, 2019. If you encounter a vehicle with Torque Converter Clutch (TCC) Shudder prior to receiving tool kit DT-52263 please postpone the repair until you receive your tool kit. Performing repairs other Aug 5, 2021 · Noticed the shudder at just under 1200 miles, Dec '18, purchased car new 2/18. Had oil change and 18-na-355 done 2/19 at about 1400 miles. 5575 miles now, still no shudder. Shifts perfectly, quick, crisp. Service Bulletin Bulletin No.: 16-NA-175 Date: February, 2019 TECHNICAL Subject: Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40 and 128 KM/H) at a Steady State Important: Follow the service procedures outlined in TSB 18-NA-355. Note: Required tool kit DT-52263 is shipping from Bosch.Illinois. Oct 25, 2021. #16. AngryScientist said: 18 Chevy Colorado V6/8-sp trans. 29000 miles. Just developed the dreaded, well known shudder issue on light acceleration. There is a TSB out there to flush the trans with new Mobil 1 Synthetic LV ATF HP fluid; which allegedly corrects the issue in the torque converter clutch area if the wear is ...Apr 21, 2023 · This problem currently affects 11 different models across 3 different OEM brands for the model years between 2015 and 2019. After implementing several fluid revisions, GM’s latest solution (TSB 18-NA-355) is lengthy, complicated and expensive. It If I am reading the 18-NA-355 that you posted for the c-7 corvette right, it looks likes if your corvette was made AFTER Feb. 1st of 2019 you should have the new fluid in it ? Yes, that's correct. Also 18-NA-355 TBS I posted is the latest version dated April 2020 which replaced the August 2019 version that was also posted above. TSB 18-NA-355. Note: Required tool kit DT-52263 is shipping from Bosch. All DT-52263 tool kits will ship from Bosch no later than February 14, 2019. If you encounter a vehicle with Torque Converter Clutch (TCC) Shudder prior to receiving tool kit DT-52263 please postpone the repair until you receive your tool kit. Performing repairs other Mar 29, 2023 · The TSB 18-NA-355 states that General Motors knew about the Transmission Shudder as early as 2015, but only created the TSB in August 2019, "and this shows that General Motors suppressed information and decided to send vehicles to consumers anyway. According to the TSB Cadillac, Camaro, and GMCPI1178F warns Service Technicians about premature ... 18-NA-355 TSB (Technical Service Bulletin) which I think is for the transmission fluid flush, the latest update addresses “torque converter clutch (TCC) shudder conditions on 8L45 and 8L90 ” eight-speed automatic transmissions, RPO codes M5N, M5T, M5U, and M5X. Affected vehicles include Chevrolet, GMC and Cadillac vehicles, as follows.TECHNICAL. Subject: Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40 and 128 KM/H) at Steady Speed. Attention: This Bulletin only applies to vehicles sold in the U.S., Canada and Middle East Operations (MEO). Mexico and Export Regions should follow Bulletin 19-NA-018. Brand:I've read 18-NA-177 and the older 16-NA-175 and now have found that an updated version of 16-NA-175 has this cryptic advice: Important: Do NOT replace the torque converter or transmission assembly for this condition. Engineer reviews have proven that replacing the torque converter does not provide a long-term solution to TCC shudder. If you do not get it done by then, you will have to pay for the repair yourself. Bottom Line: Free if you get the work done before the expiration date. Recalls. When cars come in for service, shops keep track of what the problems are and what customers are saying about their vehicles. When enough safety- or emissions-related problems have been ...Shudder TSB 18-NA-355 has been updated 7/19. I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done.The issue about the TCC shudder that many of us have experienced, and apparently carried over to a variety of GM models with the same trans assembly, seems to pretty accurately described in TSB #18-NA-355 (22 pages). I got the TSB number, because the dealer printed it in my service invoice (N/C, since I am under the powertrain warranty).In fact, 16-NA-175 refers readers to 18-NA-355 for service instructions. 18-NA-355 lists the PN for Mobil 1 Synthetic LV ATF HP as 19417577 for quart containers and 19417904 for 55-gal. drums but, as you stated above, both numbers are incorrect. The correct PN for the quart containers is 19353429.I've read 18-NA-177 and the older 16-NA-175 and now have found that an updated version of 16-NA-175 has this cryptic advice: Important: Do NOT replace the torque converter or transmission assembly for this condition. Engineer reviews have proven that replacing the torque converter does not provide a long-term solution to TCC shudder.Jun 13, 2019 · Join Date: Jun 2013. Location: Hackettstown, NJ. Posts: 209. After TSB 18-NA-355 Was Performed. 2018, 2SS Camaro with K&N cold air intake, flowmaster american thunderaxle back exhaust and AFM range finder. I just had the Transmission flush TSB 18-NA-355 performed today. I swear my engine and exhaust sound noticeably quieter after the flush. Feb 20, 2019 · In fact, 16-NA-175 refers readers to 18-NA-355 for service instructions. 18-NA-355 lists the PN for Mobil 1 Synthetic LV ATF HP as 19417577 for quart containers and 19417904 for 55-gal. drums but, as you stated above, both numbers are incorrect. The correct PN for the quart containers is 19353429. If your car is a 2018, it has the A8 and not the A10. The latest transmission fluid (Mobil 1 Synthetic LV ATF HP, part number 19417577, blue stripe on the bottle and not black) that actually fixes the problem came out in Jan 2019 as part of TSB 18-NA-355, so unless your A8 was flushed with this specific fluid, it can develop the shudder.Discussion Starter · Jul 11, 2021. I've read about both some quick and painless service appointments, and some not so easy ones as well. I'll drop my truck off tomorrow for the initial diagnostic, which I already know is the infamous shudder/shake. I'd also like an RFB, alignment, tire rotation, and a new TC if they deem appropriate.Noticed the shudder at just under 1200 miles, Dec '18, purchased car new 2/18. Had oil change and 18-na-355 done 2/19 at about 1400 miles. 5575 miles now, still no shudder. Shifts perfectly, quick, crisp.General Motors (GM) has been ordered to pay more than $100 million to classes of vehicle owners who argue the company sold vehicles with defective engines. A federal jury in California delivered the verdict against GM after less than one day of deliberation. It will benefit three classes of around 38,000 GM vehicle owners from California, North ...Rudy's bundled a complete 8L90 Transmission service kit for your GM Truck and SUV. Keep your transmission operating at top notch with all the necessary filters and fluids! Service your transmission with the new updated transmission fluid per GM TSB 18-NA-355. All filters and gaskets are genuine ACDelco parts.The auto manufacturers had no legal obligation to repair the cars. Technical Service Bulletins are issued by manufacturers when there is a problem found in a number of cars which does not have an ...My 2015 is torn down as we speak for the torque converter flood back. There are two different TSB's here. The fluid flush to address the shudder is 18-NA-355. Mine is in for the delayed engagement issue where after sitting overnight, when going into drive there is a 3 second delay followed by a harsh "bang" as it engages. That tsb is 16-NA-014.Rudy's bundled a complete 8L90 Transmission service kit for your GM Truck and SUV. Keep your transmission operating at top notch with all the necessary filters and fluids! Service your transmission with the new updated transmission fluid per GM TSB 18-NA-355. All filters and gaskets are genuine ACDelco parts.Mar 29, 2023 · The TSB 18-NA-355 states that General Motors knew about the Transmission Shudder as early as 2015, but only created the TSB in August 2019, "and this shows that General Motors suppressed information and decided to send vehicles to consumers anyway. According to the TSB Cadillac, Camaro, and GMCPI1178F warns Service Technicians about premature ... Bulletin No.: 18-NA-355 August, 2019 Page 15 5181401 18.4. Shut the engine off once 16 quarts of fluid have been collected. 18.5. Properly dispose of the collected transmission fluid. 19. Raise the vehicle. 20. Remove the DT-52263-2 Cooler Line Plug from rear differential and install the transmission oil cooler line using a new retainer clip. 21.Aug 30, 2019 · The latest revision of the shudder TSB (July 8 2019 : 18-NA-355 TSB) now states to go ahead and just do the flush if it has not yet been performed. This is good news, and what GM should have done from the beginning with this latest fluid if they were so confident in it. Took to Chevy dealership in Dec. of 2019 (@30,000 mi.) to have TSB 18-NA-355 performed. The. Mobil 1 Synthetic LV ATF HP transmission fluid swap was successful until last week when I hit around 52,000 mi. and the same problems began to emerge.. Just took the truck back in for service today.Apr 13, 2020 · Has the TSB 18-NA-355 Transmission Fluid Exchange fix your transmission shutter issues. We've linked to so many versions of TSBs it's easy to be looking at one when you think it's the other. I believe the one dated August 2019 is the most recent, with the last revisions in July, unless someone has found one that's even more recent. Jul 29, 2019 · I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done. Oct 4, 2017 · TSB 18-NA-355. Note: Required tool kit DT-52263 is shipping from Bosch. All DT-52263 tool kits will ship from Bosch no later than February 14, 2019. If you encounter a vehicle with Torque Converter Clutch (TCC) Shudder prior to receiving tool kit DT-52263 please postpone the repair until you receive your tool kit. Performing repairs other They were not willing to admit that this is a widespread problem. I showed them the TSB 18-NA-355 that describes the problem. They said a new TSB was released in 2022, TSB 16-NA-361, where it states that this is normal operation and replacing any transmission components will not resolve the problem.Sep 6, 2019 · My car was due for an oil change so I thought I would get the Thunk taken care of. I went in armed with the TSB #18-NA-355 dealing with the triple flush of fluids. However, the Corvette Tech specialist at the dealer said he would perform a complete diagnostic test before considering the TSB. GMC TSB 18-NA-355 Make: GMC Number: 18-NA-355 Title: Shake And/Or Shudder During Light Throttle Acceleration Between 25 And 80 Mph (40 And 128 Km/H) At Steady Speed Date: 1/17/2019 Models: 2017-2019Canyon 2018-2019Canyon All Terrain 2017-2019Canyon Denali 2017-2019Canyon SL 2017-2019Canyon SLE 2017-2019Canyon SLT 2015-2018Sierra 1500Title: #18-NA-355 - Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40 and 128 KM/H) at Steady Speed - (Mar 30, 2020) Vehicle: 2017 Cadillac ATS The document preview is shown on the right. To view the entire document you need to have a subscription. Subscribe Mar 29, 2023 · The TSB 18-NA-355 states that General Motors knew about the Transmission Shudder as early as 2015, but only created the TSB in August 2019, "and this shows that General Motors suppressed information and decided to send vehicles to consumers anyway. According to the TSB Cadillac, Camaro, and GMCPI1178F warns Service Technicians about premature ... If I am reading the 18-NA-355 that you posted for the c-7 corvette right, it looks likes if your corvette was made AFTER Feb. 1st of 2019 you should have the new fluid in it ? Yes, that's correct. Also 18-NA-355 TBS I posted is the latest version dated April 2020 which replaced the August 2019 version that was also posted above. Bulletin No.: 18-NA-161 October, 2019 Page 3 Correction 1 Important: The following steps must be completed in order. Grasping or attempting to rotate cables could affect readings and should be doneafter performing the voltage drop measurement. Note: When checking voltage drop, the voltage drop should be performed with the fuelJul 29, 2019 · Shudder TSB 18-NA-355 has been updated 7/19. I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done. Apr 21, 2023 · This problem currently affects 11 different models across 3 different OEM brands for the model years between 2015 and 2019. After implementing several fluid revisions, GM’s latest solution (TSB 18-NA-355) is lengthy, complicated and expensive. It Page 2 March, 2019 Bulletin No.: 18-NA-355 Shudder Test Refer to the table below for conditions pertaining to specific applications. In each vehicle, constant throttle input on a smooth grade is desirable. PicoScope Measured Frequency is the approximate vibration frequency where TCC Shudder can be found, discussed in detail below. Mar 29, 2023 · The TSB 18-NA-355 states that General Motors knew about the Transmission Shudder as early as 2015, but only created the TSB in August 2019, "and this shows that General Motors suppressed information and decided to send vehicles to consumers anyway. According to the TSB Cadillac, Camaro, and GMCPI1178F warns Service Technicians about premature ... As of August 7th, GM dealers should also be flushing all potentially affected new vehicles on the lot. According to TSB (Technical Service Bulletin) 18-NA-355, the latest update addresses “torque converter clutch (TCC) shudder conditions on 8L45 and 8L90” eight-speed automatic transmissions, RPO codes M5N, M5T, M5U, and M5X.Transmission flush fixed the shudder. (Tsb 18-NA-355) Took my 2018 Colorado WT in for the flush at the Chevy service center I get all my routine work done at. It was all covered under warranty as I only have 18,900 miles on it. Glad the flush fixed the issue. Runs smooth now, and the shifting is like night and day. The whole process took about ... Helpful websites. 18-NA-177 - RevBase - Chevrolet Bulletin RE: Procedure to confirm that shudder in Chevy Colorados and GMC Canyons is transmission related and if confirmed, directive to effect ...Dec 13, 2018 · I just took my vehicle into the dealership and they performed the testing required per TSB 18-NA-355. They could not get the pco-scop to register a high enough vibration so they would not warranty the repair. I believe this was because the last TSB 16-na-175 fixed most of the vibration and the small vibrations would not register per 18-na-355. Helpful websites. 18-NA-177 - RevBase - Chevrolet Bulletin RE: Procedure to confirm that shudder in Chevy Colorados and GMC Canyons is transmission related and if confirmed, directive to effect ...Feb 24, 2021 · This video is just a walk through of what you might be dealing with if you feel an unusual shudder.Subject: Shake and/or Shudder During Light Throttle Acce... Sep 1, 2020 · #18-NA-355 is the procedure that fixed my shudder issue. It took me three trips to the Dealership, and a test drive by the Service Manager for them to perform the TSB. 2017 Colorado Z71 V6 4WD Crew Cab -Leer bed cap.
If I am reading the 18-NA-355 that you posted for the c-7 corvette right, it looks likes if your corvette was made AFTER Feb. 1st of 2019 you should have the new fluid in it ? Yes, that's correct. Also 18-NA-355 TBS I posted is the latest version dated April 2020 which replaced the August 2019 version that was also posted above.. Bundeswehr frankfurt am main
Sep 6, 2019 · My car was due for an oil change so I thought I would get the Thunk taken care of. I went in armed with the TSB #18-NA-355 dealing with the triple flush of fluids. However, the Corvette Tech specialist at the dealer said he would perform a complete diagnostic test before considering the TSB. Dec 13, 2018 · 18-NA-355 and 19-NA-121 have been updated effective July 9, 2019 to eliminate the diagnostics portion within the TSB's and the labor times have been updated to reflect the removal of the diagnostic procedures. Vehicles presented with suspected shudder within the published build dates should have the prescribed fluid exchange procedure performed. May 6, 2022 · The issue about the TCC shudder that many of us have experienced, and apparently carried over to a variety of GM models with the same trans assembly, seems to pretty accurately described in TSB #18-NA-355 (22 pages). I got the TSB number, because the dealer printed it in my service invoice (N/C, since I am under the powertrain warranty). GM issued a Technical Service Bulletin TSB 18-NA-355, with updates that address the “torque converter clutch (TCC) shudder conditions.” The problem was identified by many customers who reported the transmission shuddering frequently and shifting harshly between first and second gear.Bulletin No.: 18-NA-355 April, 2020 Page 3 4733125 • DT-45096-31 TransFlow Adapter (one of two pieces from DT-45096-30) Service Procedure Initial TransFlow Flush Machine Setup Important: The prepping procedure only needs to be completed if the DT-45096 supply reservoir has DEXRON VI fluid in it and has not been converted to Jul 29, 2019 · I just caught wind of a very important update to the transmission shudder TSB. Apparently, as of July 9th, the TSB has been revised to no longer require diagnostic procedures. This is obviously big news for those of us who have had to jump through dealer hoops to get anything done. BigTallVandy said: TSB's are simply guidance documents to assist service personnel in quickly diagnosing and repairing previously identified issues. They are not related to a vehicle's warranty. If a problem is addressed by a TSB and the vehicle is still under warranty, it is repaired free of charge to the owner.Aug 5, 2021 · Noticed the shudder at just under 1200 miles, Dec '18, purchased car new 2/18. Had oil change and 18-na-355 done 2/19 at about 1400 miles. 5575 miles now, still no shudder. Shifts perfectly, quick, crisp. Noticed the shudder at just under 1200 miles, Dec '18, purchased car new 2/18. Had oil change and 18-na-355 done 2/19 at about 1400 miles. 5575 miles now, still no shudder. Shifts perfectly, quick, crisp.Shake and/or Shudder During Light Throttle Acceleration Between 25 and 80 MPH (40 and 128 KM/H) at Steady Speed. Attention: This Bulletin only applies to vehicles sold in the U.S., Canada and Middle East Operations (MEO). Mexico and Export Regions should follow Bulletin 19-NA-018.Sep 12, 2021 · According to the Technical Service Bulletin (TSB 18-NA-355), flushing factory-used transmission fluid and swapping it for Mobil 1 Synthetic LV ATF HP fluid may improve the situation. If there is no noticeable improvement after transmission fluid flush, the torque converter could be glazed, especially if it was used with this issue for a long time. Dec 13, 2018 · Hi John. My local GM dealer recently (1/24/19) diagnosed my 2016 Camaro SS with the same code as your Corvette (18-NA-355). I google searched it and found your post. They flushed and changed my transmission oil (13K miles) and the shudder has greatly improved. However, I am noticing some new hesitations as the transmission shifts in lower gears. .