Will ATF change stop tranny slipping? ('92 GeoPrizm)

[FL-400S]

My folks have a '92 Geo Prizm (Corolla) that I originally bought used for my then girlfriend (now wife). My wife got a new car and my parents bought the prizm from her. The car has a rebuilt title from front end damage, though we dont know much about it. Aside from needing CV joints, the 3 speed auto transmission seems to slip, and on VERY cold days it sometimes wont shift out of park. You can move the shifter, but then when you step on the gas, it just barely goes, like its not fully engaged. That only happens when its below freezing outside. The transmission fluid has not been changed since we got the car over 2 years ago. It had 62K at the time and now about 76K miles. Transmission fluid could be original, I have no idea. Would putting new fluid help out? Flushing is out of the question, unless I can do it in the driveway. My dad wont even change the CV joints, since he does not want to spend $500 on a $1000 car. If we can get the transmission in better shape, he might pay for CV joints. AutoRX might be out too, because the CV joints may not last 1000 miles. So what to do in this situation?

 

[TheJMan19]

What I would do is drop the pan, replace the fluid that is in the pan with a quality dino like Chevron, and change the filter and gasket. Drive on it for a week or so, drop the pan again, and just replace the fluid. I did this on my Explorer and while I wasn't having any transmission problems, it defintely improved the shifting.

 

[Jelly]

Yeah...the fluid is most likely very old and has highly degraded cold pumping properties, causing the shifting problems you mentioned.

Buy some ramps if you don't already have some and follow JMan's advice.

You'll be amazed how much better the transmission will operate with a few simple fluid changes!

[ May 31, 2004, 01:01 AM: Message edited by: Jelly ]

 

[JohnBrowning]

Get remaned CV joints from a parts store. Change fluid in transmission first and see if that does not do it. If it still has a problem try Auto-Rx. THe only way this transmission is shot is if it has many more miles then the rest of the car has. Have checked the shifter cable to make sure it is adusted right?

I know I am going to get flamed for this but oh well! If the seals are in good shape and you think that light varnish from lack of regular fluid chages is causeing the transmission to malfuntion then Trans-X witch is a cheap solvent based cleaner works well!

I prefer to drain the old fluid out and refill with clean fluid before adding the Trans-X. If it is going to work it will do soo in 500 miles or less. If it has not helped then drainit out and refill with clean fluid.

You really do not want to leave solvent type products in a transmission any longer then needed.

[ May 31, 2004, 01:12 AM: Message edited by: JohnBrowning ]

 

[VaderSS]

quote:

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Get remaned CV joints from a parts store.

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I've installed a few CV joints, but I gave that up. Messy and any contamination will drastically shorten the life of the CV joint. I now prefer just getting a complete half-shaft. Usually not that much more, and eliminates a few steps.

 

[unDummy]

Once a transmission starts slipping, its on it way out.
This doesn't mean that a ATF change won't help. If anything, it might extend the life of the transmission a little.

If you have a drainplug for the ATF, then perform a drain/refill.
If the transmission performance improves, do another in a week or so.
If no drainplug, then running engine with ATF coolant line disconnected is an option. Or better yet, make or buy an oil extractor like the Pela. The ATF can be siphoned, from the dipstick, with patience, gravity, and a plastic tube/hose from the hardware store.

Reman axleshafts are about $60 apiece. The factory service manual or chiltons/haynes/mitchell books would help you with the removal/install if you have tools and mechanical experience.
Also, any needed transmission adjustments, will be covered in the FSM.

 

[FL-400S]

It turns out my dad does not want the car anymore and will give it to me to add to my fleet. We are going to do the axle halfshafts on our own using the 1992 service manual. They are only $60 a piece and apparently its pretty easy once you know what you are doing. Then Ill drive it the 200 miles to my place and worry about the transmission. I think its got some good miles left, but if the transmission drops, Im not putting a new one in. I hate automatics on economy cars anyway.