Tranny problem

[Chinski]

I have a 90 Lumina EuroSport that is almost at 200,000 miles. Original tranny and engine. Recently it has been not wanting to shift out of first and second untill real high RPM's. It stays in 1st up to 5+K and 4+K before coming out of second. This problem goes away after things warm up after a 5-10 minutes of driving. I figured I was low on fluid so I checked it and it was at the bottom of the cross-hatch marks. I filled 'er up and it helped some, but it still does it althought not quite as high RMP's before shifting. And like I said, it shifts like normal after it has warmed up. Any ideas? I'm due for a fluid and filter change, so I'll have that done when I take it in to get my breaks looked at. It seems like if it were the tranny going it would do it all the time, not just when cold, but I really don't know. If it comes down to needing a tranny I don't want to spend $1000 for a rebuild for a car that has so many miles on it. Would a used tranny from a yard be a reasonable idea or cheaper? I have the 4t60 and not the 4t60E right? How much of a difference does this make for availability and such?

[Redfox340]

I would flush out the fluid... especially if it's discolored or smells burned. Since tranny fluid is a hydrolic detergent, it keeps metal shaving suspended in the fluid until it passes by a magnet on the bottom of the tranny pan. After time, the fluid losses it's propeties and all the particles begin to collect in different area creating sloppy shifts and 'slipping'. Try that... if you're up to it... have a little home project to save some cash!!!

 

http://redfox340.tripod.com/wbodyperformance/id18.html

 

- RedFox340

[arvetus]

Flush the fluid and change the filter. Sometimes the metal shavings will collect in the filter and other places in the transmission like the last guy said, causing rough shifting. It could also be an engine temperature issue. I had a similar problem with my regal which has the same engine and tranny and it turns out the thermostat was stuck open, never allowing the engine to warm up properly, which may be why it doesn't happen after you drive for 10 minutes. My problem was having to do with never going into overdrive/lockup, so the problem was a little different, but somewhat similar. With that engine and tranny, the engine has to warm to 164 degrees before the tranny will idealy function. I'm not saying it's the solution, but just something to check. If no one can find anything wrong at a shop, your best bet would be to take it to a dealer that can track down the problem to the wire with their handy dandy expensive GM diagnostic computer. If you have them fix the problem, usually they will deduct the diagnostic test from the labor to fix it. Plus, if they don't fix it the first time, you're not liable to pay them to fix it again if it still doesn't work. If you do it yourself, you could spend a lot of money in parts that might not be the problem. And if you take it to a fly-by-night garage, unless it's someone you trust and know pretty well, they can charge you for whatever, no matter if it fixes it or not. That's the problem with these new fangled computerized engines. 9 times out of 10, it's not a mechanical failure. :?

[GnatGoSplat]

I have a similar problem with my '89, but only if ambient air temps are below freezing.

You might try a transmission additive. I believe this is happening because rubber seals or perhaps even the clutches on the bands have hardened due to age and don't soften up until they get warm.