tranny / torque converter problem?

[kaspr]

Hello everyone,

I have a 2003 Silhouette with 139,000 miles. Recently I've noticed a problem with the tranny, only when stepping on the gas immediately after shifting into gear (either drive or reverse). Otherwise, the tranny is operating great and smooth, and shifting is flawless. The fluid is clean and at a good level and as far as I know the tranny has not been abused. No trouble codes.

OK, so here's the issue. When I shift into drive or reverse, the tranny does go into gear immediately like it should. If I were to leave my foot off the brake pedal, the van starts to move immediately after shifting. However, some of the time, when I step on the gas immediately after shifting (within 1 second), the van only moves a tiny bit until the torque converter kicks in and the van "jolts". If I were to wait 2 seconds after shifting, this doesn't happen and the torque converter applies power immediately when stepping on the gas.

This problem happens intermittently, both when the engine/tranny are hot and when they're cold. If I am parked and shift into drive, it might work fine, and then if I do it again, it has the delayed response, and then if I do it again, it might be fine again. There's no rhyme or reason. I have noticed that it has this problem more often when going from reverse to forward or forward to reverse. The problem occurs less often when going from Neutral to forward or reverse.

I hope this explanation helps. I don't have a very good understanding of how the tranny and torque converter work together, but I suspect it's a torque converter related issue.

Any ideas?

[maxwedge]

Excellent description, wish we all had this when replying to posts. Only a pressure test done under these conditions can really pick out the problem, sounds like a delay in pressure reaching the clutch pak which could be a seal leaking or some other internal press. loss.

[kaspr]

what tool would test pressure? Is that a dealer-only tool or can I buy one?

Is it relatively easy to test pressure or are we talking $100+ just for them to test?

[maxwedge]

First you need to find out which pressure port to test, there are 2 or 3 on the trans, then you need the gage with the proper connections. Maybe better to have it done, these probably would be one time use tools for a DYER.