Vibration at 30 mph on decel

[trp34g]

202 Silverado 1500 5.3, 8-speed. I get a vibration at 30mph while decelerating. Does not do it in neutral. Feels like DFM is causing it. Not TCC Shudder as I understand it. Taking to dealer tomorrow for this problem as well as hot trans while towing (240+ F). Have seen the TSB regarding Cam Actuator Magnet, but would like to make any other suggestions to service desk tomorrow. Thoughts?

[Bikerjon]

5 hours ago, trp34g said:

202 Silverado 1500 5.3, 8-speed. I get a vibration at 30mph while decelerating. Does not do it in neutral. Feels like DFM is causing it. Not TCC Shudder as I understand it. Taking to dealer tomorrow for this problem as well as hot trans while towing (240+ F). Have seen the TSB regarding Cam Actuator Magnet, but would like to make any other suggestions to service desk tomorrow. Thoughts?

What year is your truck? Its not a 202. How many miles? Some of the earlier T1s used a defective trans. fluid that needs to be replaced and flushed out. If you have this service done make sure they replace the trans. filter.

[trp34g]

Sorry. 2020. 43000 miles. 

[Bikerjon]

Take it to a dealer, it probably needs the tranny flush. They can diagnose your problem better than someone on an internet forum. Make sure to take the tech on a road test and demonstrate your issue.

[silveradosid]

check the build date on your truck, you might already have the updated fluid. i got sucked in by the dealer for this and found out later my truck had the new fluid and changing made no difference