1G Auto Tranny Slipping

[psiboost]

Hey guys -

I read up on the auto tranny section of the forums, and I just wanted to confirm what is causing the issue I am having.

1993 Eclipse NT w/orginal tranny @ 114k

Trans started slipping early this year when the car was generally cold start. I would get up to around 30mph - then on occasion it would slip, and to reengage, I would let off the gas and the trans would slip back in. This happened every once in awile.

More recently, this started happening every week or so. The old method of letting off the gas would no longer solve this problem. Now, I would have to shift to 2 or L, then back to drive...in which then the problem was solved.

This week, that trick no longer worked. I am able to pull out of my spot cold, and I get up to around 35/40 and the trans slips. The only way to re-engage it is if I turn overdrive off. Of course I don't want to drive with OD off, but it the only way I can get my car to move.

Therefore, it looks like the car will be down until I can resolve this. From talking to local DSM guys, it appears that I will need get a clutch kit as mine clutch is worn out.

Is there anything else that could be going wrong that would cause this? I can only hope it is the clutch, as from what I am told, they are pretty simple to do on this trans.

Additionally, for those here that have replaced the clutch, what are some places recommended? This is my daily driver, so I don't need high performance.

Thanks

 

[blackbyrd]

Which clutch are you referring to? just the Torque convertor?
I had a very similar problem, but it only happened when it was cold(really cold) outside. under about 5*F it was impossible to get my car in gear, or a half a mile down the road it'd slip out, and id have to come to a stop and try shifting to get it to re-engage. Once my car was heated up normal it never had a problem, except when this idiot underfilled my A/T fluid, long story. Anyways, I took it to a guy i know at aamco, and after checking it out he said he couldn't find anything physicaly wrong with it, and it was probably just the seals in my transmission, allowing blow-by happening durring a cold shrunk gasket.
Re-reading your post
when your slipping at 35mph, are you in Overdrive? Are you talking about replacing your end-clutch?
Which is rather easy to do..
Check out IPT,www.importperformancetrans.com

 

[psiboost]

Forgive my tranmission ignorence - but are end clutch kits only for automatic trannys?

 

[psiboost]

when your slipping at 35mph, are you in Overdrive? Are you talking about replacing your end-clutch?
Which is rather easy to do..
Check out IPT,www.importperformancetrans.com

Yes, the OD is on when the car starts to slip...shutting it off is now the only way the car will engage.

The problem sounds similar to yours, except mine is not ambient temp specific. It happens when the car has been sitting all day in 90 degree heat or when I fresh start it in the morning after a 50 degree night. It used to only happen in the first few minutes of driving after the car was sitting for an extended period of time. I assume that it stopped slipping after those few minutes due to the AT fluid heating up as well as the metal components (which would of course expand due to heat).

But now it doesn't matter if the car has been sitting or driving for 20 minutes, the car pretty much doesn't like to be driven with OD on. The trans will engage from a standstill in OD, but pretty much slips as it reaches around 3rd gear or so.

Although I consider myself mechanically inclined, I have never tinkered with transmissions. Hence the reason I am having a problem diagnosing the problem at hand. I have a great DSM mechanic, but he only specializes in manual trannys, so he sent me here to check with you guys. From what I told him, he thinks all things point to the end clutch going bad.

So with all the symptoms that I am experiencing, can it be the end clutch solely, or a combination...or perhaps something else altogether? I need to get this car up and running asap due to me using it for my 100 mile/day commute. Using the car with OD off is wrecking havoc on my tranny - so it just sits in my driveway until I can fix.

 

[blackbyrd]

If it ONLY slips while in OD, then I would say its your end clutch. I had that problem with mine when i first bought it, although it only happened a couple times in OD, and I think it was when I tried to Downshift from OD or sometimes upshift to, it'd immediately shift out. Prompted me to replace my endclutch, and it hasn't done it since. Check out IPT, they have a good end clutch kit for 79$.. And its pretty easy to replace.
If it's slipping outside of OD you might have some more problems..
Another good practice for OD is to only engage it when your going over 45-50+mph. Putting it in overdrive before then will add a lot of unneseccary stress, as it's trying to spin harder to keep up.

 

[psiboost]

I ended up ordering the IPT End Clutch Kit based on your observations and what I have been told by my DSM guy...so thanks. I also downloaded the VFAQ on the installation process (although it is labeled for an Alto kit...not sure if that is what I ordered?).

Regarding your statment of not using OD in lower gears, I'm a bit confused. Whenever my OD is off, there is a subsantial strain on the engine with the higher RPMS, and I assume the same holds true for the tranny. Is this not correct? Even though my engine is reving higher, is OD off really better for the tranny?


One more thing - is there anything else I should check out while I have the clutch cover off...or any special tricks I should know?

 

[blackbyrd]

The OD is basically your 4th gear. It should only be shifted into from 3rd gear(you said something about other gears), and only at a good rolling rate. It allows your engine to rotate less while giving the same revolutions to the wheels. However you must be at a good rolling rate to utilize it, so it doesn't put additional stress on your engine... IE at 35 trying to accelerate in OD will rotate the engine and transmission more trying to keep up, then if you were in 3rd.. Its really not a power/accelerating gear. And if your racing it's best to stay out of it in my experience.
And you were speaking of RPMs, if your in third gear, at anything over 4k rpms, you should be doing at least 45... So engage it.. Not sure what all you meant(by high rpms etc), but I did my best to explain it, as it was explained to me.

And you could go ahead and replace your at filter/pan gasket, and fluid.

 

[psiboost]

I ended up replacing the filter, pan gasket and of course the end clutches and seals.

Put everything back together and the car still slips when I get up to about 30 mph using moderate acceleration.

When I floor it, the car doesn't slip (w/OD on).

More investigation is needed - perhaps this issue is larger then just the end clutch - which I hope is isn't.

 

[blackbyrd]

hmm.. Okay, quick question, when it slips at 30mph, are you in the 4th(overdrive) gear?
Are you in a lower gear, but still have the OD button pressed on?
If the OD button is off, will it still slip?
I'm sorry to hear about your luck, i'll try my best to help.
And have you got an accurate balance of ATF in there?

 

[autonut]

Sorry to chime in so late, but the 4th gear clutch is a classic problem with the KM series auto transmissions. Ive repaired 3 cars in the last year that had a burned up "end clutch", but with rebuild kit that is readily available, you should be able to easily resolve without pulling the unit. Its pretty cool that its right inside the passenger wheel well.

Keep in mind tho, that all that debris from that gear housing is all thru the trans. You really should take out the vavle body, disassemble it, and clean it. May as well install a translab or transgo shift kit while your in there if you havent already.

Ive messed with these transmissions for years and have yet to have 2 operate the same way. Something about the aluminum valve body that varies its operation depending on the fluid temp.

If you need any overdrive parts, hit me up, I have extras. Another suggestion, the 89-91 Hyundai sonatas have a 4 clutch overdrive, as opposed to your 3 clutch overdrive. They are interchangeable as long as you have the outer cover.

 

[blackbyrd]

Sorry to chime in so late, but the 4th gear clutch is a classic problem with the KM series auto transmissions. Ive repaired 3 cars in the last year that had a burned up "end clutch", but with rebuild kit that is readily available, you should be able to easily resolve without pulling the unit. Its pretty cool that its right inside the passenger wheel well.

Keep in mind tho, that all that debris from that gear housing is all thru the trans. You really should take out the vavle body, disassemble it, and clean it. May as well install a translab or transgo shift kit while your in there if you havent already.

Ive messed with these transmissions for years and have yet to have 2 operate the same way. Something about the aluminum valve body that varies its operation depending on the fluid temp.

If you need any overdrive parts, hit me up, I have extras. Another suggestion, the 89-91 Hyundai sonatas have a 4 clutch overdrive, as opposed to your 3 clutch overdrive. They are interchangeable as long as you have the outer cover.

He already replaced the end clutch.. It's still acting the same.
Didn't know that about the hyundai's OD, interesting.. Is the 4 clutch od better?

 

[psiboost]

hmm.. Okay, quick question, when it slips at 30mph, are you in the 4th(overdrive) gear?
Are you in a lower gear, but still have the OD button pressed on?
If the OD button is off, will it still slip?
I'm sorry to hear about your luck, i'll try my best to help.
And have you got an accurate balance of ATF in there?

Here is what I have experienced with a 20 minute post-repair drive:

When I start the car w/OD on, using normal acceleration, the trans slips at around 30mph (which I believe is 3rd gear?) and just revs until...

I turn off OD, and the trans re-engages which then I can drive at any speed.

However - if I floor it from a stop, I can accelerate past 30mph w/OD on - I got up to around 55mph, held it study for a few seconds and then the trans slipped.

From what I understand, is that when you slowly accelerate like I originally did, the OD kicks on early...when you floor it, the OD doesn't kick on until you stabilize your speed.

I have checked ATF - it appears that it is at the right level. I did the whole PRND2L twice over and back to N, then checked. The level appears between the 'hot' markings on the stick.

In the process of changing the end clutch, I also replaced the trans filter and pan gasket. I didn't notice any debris in the pan, and the fluid was a dark dark red/brown, but not burnt.

 

[psiboost]

Sorry to chime in so late, but the 4th gear clutch is a classic problem with the KM series auto transmissions. Ive repaired 3 cars in the last year that had a burned up "end clutch", but with rebuild kit that is readily available, you should be able to easily resolve without pulling the unit. Its pretty cool that its right inside the passenger wheel well.

Keep in mind tho, that all that debris from that gear housing is all thru the trans. You really should take out the vavle body, disassemble it, and clean it. May as well install a translab or transgo shift kit while your in there if you havent already.

Ive messed with these transmissions for years and have yet to have 2 operate the same way. Something about the aluminum valve body that varies its operation depending on the fluid temp.

If you need any overdrive parts, hit me up, I have extras. Another suggestion, the 89-91 Hyundai sonatas have a 4 clutch overdrive, as opposed to your 3 clutch overdrive. They are interchangeable as long as you have the outer cover.

Autonut -

Thanks for the info - as blackbyrd said, I have replaced the end clutch and seals (IPT kit) yet have not noticed a change at all in the trans behavior...just as if I never replaced anything.

What I did notice was that one of the discs (or perhaps plates) was really warped, and the seal that goes around the piston was somewhat shredded. So I thought for sure that I would solve the problem by replacing it all.

I'm interested in any suggestions...how difficult is the removal and cleaning of the valve body? Even though I saw no debris in the pan, you think that this could be a source of the problem?

My friend mentioned that it might be the trans pump as well - which I know would pretty much spell the end of ever fixing the problem w/out spending lots of $$$.

 

[psiboost]

any other thoughts on this issue?

 

[95TalonOwner]

When mine started doing this on my 91 last winter, it just kept getting worse and worse until eventually it wouldn't work at all no matter what I did. I ended up getting a used rebuilt tranny for 250 bucks and that solved my problem.

 

[blackbyrd]

Hey man, I'm taking a look over all the posts. Sorry, I haven't been able to get to it sooner. Responding from your PM's. I don't understand why John at IPT said "it isn't 4th gear, 4th gear is only when OD is active" Yet, it's only happening going into 4th gear when OD is active.. He might not have understood you too well.

Some quick thoughts..
1>Is this for a 1.8l or 2.0l N/T?
2>Try adding a little more tranny fluid, even though you said it was between the hot markings, bring it up to the top line.
3>Do you happen to have any pictures?
4>Do you want to take out your new OD and see if the plates in it are warped again? And just to double check all of the work.
5>First, what plate are you talking about?
6>If the seal that went around the piston was somewhat shreaded isn't it possible that it's made it's way through into the transmission?
7>It might be an alright idea to clean your valve body, It isn't too difficult either, you have to drop the pan. I would say flush the hole transmission, but sometimes powerflushing an old transmission that's damaged, can cause more damage, as most shops will have to do preinspections first to determine if they will.
8>Was it the inner or outter piston seal? Did you put transmission fluid or vaseline on them to help them seal?
9>Did you make sure you put the outter seal on the right way?
10>Did you notice this?
Your kit should have 2 metal clad seals. The reason is because in 1992 (06/92) they changed the inner shaft diameter. They both have the same outside diameter but the inner seal is smaller on the later models. The outside seal diameter is the same so either will fit in the end clutch drum.
So, the later will not fit on the earlier shaft (too small) but the earlier will fit over the new shaft but be too big. This will cause a leak and ultimately failure. So put them side by side to check and make sure it its on the shaft securely.
>Did you use the earlier/larger one?
11>Have you tried using a voltimeter and reading your TCU, to see if you have any fault codes?

.Here's some more possibilities:
12>Improper adjustment of Manual linkage
13>Low Fluid Level
14>The piston in your End Clutch(check ball hole)
15>Malfunction of inhibitors switch, damaged or disconnected wirring, or improper adjustment
16>PCSV(Pressure Control Solenoid Valve) Damaged or disconnected wirring (valve open)
17>Malfunction of transaxle control unit

18>What is the color of your AT fluid? Is it really dark, or blackish almost? Does it smell burnt?


Well that should keep you busy for a little while. It's getting late, I'm getting tired.
Let me know when you've gone through that list. Try to respond to everything the best you can..
Good Luck!

 

[psiboost]

ok from your questions I can answer the following at this point:

1>Is this for a 1.8l or 2.0l N/T? 2.0 n/t

3>Do you happen to have any pictures? I have the plates/discs out which I can take pictures of, what else would you need to see?
5>First, what plate are you talking about? if I remember correctly, it was the 3rd
6>If the seal that went around the piston was somewhat shreaded isn't it possible that it's made it's way through into the transmission? well, there weren't large pieces missing...just shreded like string cheese...plus with the piston pressed against the housing, I can't see how any pieces could get loose
7>It might be an alright idea to clean your valve body, It isn't too difficult either, you have to drop the pan. I would say flush the hole transmission, but sometimes powerflushing an old transmission that's damaged, can cause more damage, as most shops will have to do preinspections first to determine if they will. any hints on how to clean the valve body?
8>Was it the inner or outter piston seal? Did you put transmission fluid or vaseline on them to help them seal? the large outer seal, and I lubed it up
9>Did you make sure you put the outter seal on the right way? I hope so per the instuctions...what is the 'wrong way'?
10>Did you notice this?
Your kit should have 2 metal clad seals. The reason is because in 1992 (06/92) they changed the inner shaft diameter. They both have the same outside diameter but the inner seal is smaller on the later models. The outside seal diameter is the same so either will fit in the end clutch drum.
So, the later will not fit on the earlier shaft (too small) but the earlier will fit over the new shaft but be too big. This will cause a leak and ultimately failure. So put them side by side to check and make sure it its on the shaft securely. It looked the same as the old one - I had to tap it in lightly w/force but it was evenly secure
>Did you use the earlier/larger one?
11>Have you tried using a voltimeter and reading your TCU, to see if you have any fault codes? no, I'll do that this weekend

18>What is the color of your AT fluid? Is it really dark, or blackish almost? Does it smell burnt? it was dark dark red...prior to this I had a slight pan leak, so I added a qt every couple of months or so...it did not appear burnt nor where there any shavings in the pan