Tranny Slipping Initially Then Fine

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GT6ixer
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Tranny Slipping Initially Then Fine

Post by GT6ixer »

All great crops start first by sewing some seeds. So let me contribute to this 928 Farm by posting my first tech question.

As the title states in the last 6 months or so, my ‘84 (best MY btw) auto started to exhibit transmission slippage immediately and only after sitting overnight or many hours between driving. Get up in the morning, start the car, pull away and the car surges in rpm but barely moves and wont get out of first gear until about 5 seconds later. It will continue this behavior into 3rd gear. Once at speed shifts from 3rd to 4th are fine. Now the strange part. This behavior only lasts for about the first mile of driving then it shifts perfectly the rest of the drive. I would say maybe its related to transmission fluid temperature but since it only lasts a mile (or about 5 minutes after startup) I doubt there would be much temperature change correct?

Any ideas?

Thanks!

Nate
Daniel5691
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Re: Tranny Slipping Initially Then Fine

Post by Daniel5691 »

Hello sir !
Is it possible that the ATF level is low?
I had an older car one time that did the same when low, just as you described. Might be a super easy thing to check first...
Thanks Dan
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Re: Tranny Slipping Initially Then Fine

Post by Mongo »

You can check the ATF level cold by starting the car, then crawl under and take a peak at the reservoir. There are three levels. After 2 minutes of idling, put the car in reverse for 15 seconds, then drive for another 15, and back to park. The fluid level should be at the bottom line. This is a good start to determine whether you need to add.

After a 10-15 min drive, the level should be at the second mark or likely just below the top of warmed up. There is not much gap between the two top lines.

I have corrected an S4 at a cold level just by following the steps in the first paragraph. Good luck.
Andy

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SeanR
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Re: Tranny Slipping Initially Then Fine

Post by SeanR »

3 or 4 speed?

Must disagree on one point. '88 is best year. :)

Def check the fluid and if you've not done a fluid/filter change, that would be the first thing on my list to get done then report back. Even a couple quarts low will cause odd actions.
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amdavid
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Re: Tranny Slipping Initially Then Fine

Post by amdavid »

.....and? Results?
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GT6ixer
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Re: Tranny Slipping Initially Then Fine

Post by GT6ixer »

Thanks guys. I haven't had a chance to check the level but I need to soon. I think I jinxed myself with this thread. I went for a drive this past Sunday and after about 20 minutes it wouldn't shift out of 1st gear. Visited a friend few a few hours abd when I left it shifted fine all the way back home. It's in the garage now. Hope to get to it this week and will report back.
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Re: Tranny Slipping Initially Then Fine

Post by GT6ixer »

Image

So got to checking the fluid levels per your guys' suggestions and it was about a quart low. It was simple enough to fill through the reservoir parked on a level surface and without jacks. I used a $7 quart pump adapter from AutoZone and filled it with some Lucas ATF fluid. Then took itfor a nice 20 minute drive to get everything warmed up and checked the level again and it was fine. I've been driving it for the past week and it shifts good now. This winter I'll go and do a proper fluid flush and filter change. Thanks again for the help and advice.
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Re: Tranny Slipping Initially Then Fine

Post by SeanR »

GT6ixer wrote: Tue Sep 01, 2020 8:38 pm Image

So got to checking the fluid levels per your guys' suggestions and it was about a quart low. It was simple enough to fill through the reservoir parked on a level surface and without jacks. I used a $7 quart pump adapter from AutoZone and filled it with some Lucas ATF fluid. Then took itfor a nice 20 minute drive to get everything warmed up and checked the level again and it was fine. I've been driving it for the past week and it shifts good now. This winter I'll go and do a proper fluid flush and filter change. Thanks again for the help and advice.
That looks like 2-3 quarts low. Did you check it running?
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Re: Tranny Slipping Initially Then Fine

Post by worf »

SeanR wrote: Tue Sep 01, 2020 9:50 pm That looks like 2-3 quarts low. Did you check it running?
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Charlie
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Re: Tranny Slipping Initially Then Fine

Post by Charlie »

FWIW, my dad's '69 Impala had the exact same problem and solution. There is nothing new under the sun.
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GT6ixer
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Re: Tranny Slipping Initially Then Fine

Post by GT6ixer »

Yes. I took that pick while it was running. I filled it up while the car was idiling to the 20deg C dot which is the bottom mark in the picture. It only took about a quart, maybe a quart and half. Since the cheapy pump I bought only reached so far into the quart of ATF, I opened up a second bottle and pumped some out of there. After I took it for a drive the level stayed at the 20deg C mark. When the car is shut off the entire reservoir gets filled up.
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Re: Tranny Slipping Initially Then Fine

Post by worf »

GT6ixer wrote: Wed Sep 02, 2020 12:23 am Yes. I took that pick while it was running. I filled it up while the car was idiling to the 20deg C dot which is the bottom mark in the picture.
FYI: WSM directs a filling procedure that includes running it through the gears while filling.
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GT6ixer
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Re: Tranny Slipping Initially Then Fine

Post by GT6ixer »

worf wrote: Wed Sep 02, 2020 12:47 am
GT6ixer wrote: Wed Sep 02, 2020 12:23 am Yes. I took that pick while it was running. I filled it up while the car was idiling to the 20deg C dot which is the bottom mark in the picture.
FYI: WSM directs a filling procedure that includes running it through the gears while filling.
While filling? Well crap that's a two person job now ain't it. I ran it through all the gears on my drive. Shouldn't that in theory push the ATF fluid everywhere it needs to go?
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Re: Tranny Slipping Initially Then Fine

Post by Shifted »

   
Last edited by Shifted on Fri Feb 12, 2021 5:12 pm, edited 1 time in total.
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GT6ixer
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Re: Tranny Slipping Initially Then Fine

Post by GT6ixer »

Ahh good info. I did basically what that said. The difference is after my drive the level was still at the 3rd mark. Likely the ATF was hotter than when I filled it to that mark after it was idling from a cold start. So after the drive I probaby should have added some more to get the level somewhere between the min and max lines. I'll check it again when I get home from work.
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Re: Tranny Slipping Initially Then Fine

Post by SeanR »

As long as you've checked it and it drives great, that is what matters. Well done.
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GT6ixer
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Re: Tranny Slipping Initially Then Fine

Post by GT6ixer »

Thanks Sean. It does make a sort of thud you can feel when down shifting from 4th to 3rd on heavy acceleration. It has always done that since I've owned it, but not sure if that's how it is supposed to be or just how it is on my car. It's not concerning as it never got more "thuddy" in the 12K miles I've put on it thus far.
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Re: Tranny Slipping Initially Then Fine

Post by SeanR »

GT6ixer wrote: Wed Sep 02, 2020 5:00 pm Thanks Sean. It does make a sort of thud you can feel when down shifting from 4th to 3rd on heavy acceleration. It has always done that since I've owned it, but not sure if that's how it is supposed to be or just how it is on my car. It's not concerning as it never got more "thuddy" in the 12K miles I've put on it thus far.
Key thing is you noticed the slipping and stopped driving it right then, checked what was wrong and fixed it. These things do not like to slip, ruins all sorts of internals.
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