Shoutout to mechanics who have cracked cold-start transmission shudders

I run a small moving company, and one of our older box trucks has a nagging issue when the weather drops. It's a 2008 model that shudders badly for the first couple miles on cold mornings, then runs fine. We swapped the transmission fluid and put in a new filter last month, but the shake came back. It's holding up our early jobs because the drivers don't want to take it out. I'm not a transmission expert, so I'm stuck on what to check next. Could it be something simple like a mount or the converter clutch? If you've seen this, what steps did you take to find the fix? I'd really appreciate any pointers to get this truck back on schedule.

3 comments

Log in to join the discussion

Log In

3 Comments

miaw106mo ago

You mentioned mounts and converter clutch, that's exactly where I'd look next. On my work van, a cracked engine mount felt just like a transmission shudder on cold starts because everything was shifting under load. Also check the torque converter clutch solenoid, mine would stick when cold and cause a violent shake until fluid warmed up and freed it.

2

pipera506mo ago

That cold start shudder you described sounds exactly like my old truck's torque converter issue. How did you end up testing the solenoid, did you just monitor lockup pressure or swap it out first? I'm guessing the solenoid is cheaper than a mount, so maybe start there.

4

angela_chen666mo ago

My car's shudder... fixed with new plugs, @pipera50.

2