Why does the 2000+ Bonneville take so long for the TCC to lock up? A few weeks ago it was only in the 20'* and it would take more than 8 miles for the TCC to lock up at 55MPH driving speeds. It is like this on both the SLE and SSEi. The Riv on the other hand will lockup the TCC within 2 miles of driving at the same speeds. Any ideas? Even though the engine temperature reaches the 200 mark within 2 miles the transmission won't lock up the torque converter clutch for around 8.

It sint just dependent on the speed input, it also takes in to account the load that is on the engine and weather the road is flat. Plus the TCC is a free wheeling clutch, where there is no load it unlocks

I should also mention that this is all on the same roads that I got these numbers from. Just doesn't make sense why it takes so long. Gas mileage is about 4 MPG lower because it takes so long to engage.

Sounds like there'* something wrong. In my '01 SSEi, once it is up to full temp, the TC locks up right away... No waiting. If anything, I think that the TC should unlock more often for me. I tend to get a little bit of shudder going up small to moderate slops between 40mph and 50mph.

Now until the temp goes above 160* (I believe, but correct me if I'm wrong), the TC will not lock up at all to run higher rpms to get the engine warmed up faster. If you know someone with an Autotap or other similar scanner, get it scanned while driving down the road. An Autotap can see all of the TCC settings (what the comp is requesting as well as (i think) what is being given). That would be a good place to start.

I noticed this same thing when i was out in western mass. alot when it was cold. When i would start the car up and drive it would take forever for the torque converter to lock especially when it was really cold. Where i was the road wasn't very flat at all. Back at home where the roads are really flat and almost no incline it only takes a few min to kick in even when it'* cold. I thought something was wrong with mine too, but i haven't had a problem with it since. Even slight inclines didn't allow it to lock in, or when i was going down hill either. Just my experience, hope it helps.

Doesn't tranny temp have something to do with TCC?