91 Legacy 4EAT

[Twitch de la Brat]

So, my sister just bought a 91 Legacy LS Wagon with a 4EAT and it has

torque bind, but we currently have the FWD fuse in place to allow her to run

her errands without squeaking the tires around corners.

 

A little history, the tranny fluid was burnt to the point of being turned dark

brown when she bought the car, so we changed the fluid and it fixed the

hard shifting.

 

The engine runs great, decent power, the tranny shifts nicely, but it vibrates

when turning.

But only at slow speeds, and at all angles of the wheel.

If you power out of it, it goes away.

 

Any ideas?

 

I'm thinking the torque converter could be hanging up and not slipping

smoothly or a front diff issue.

 

The CV axles don't click, but I haven't gotten a chance to crawl under the

car and fiddle with them to see if there is any play.

 

Twitch

[Legacy777]

Does the vibration only happen during turns? Does it happen with the FWD fuse installed?

 

If yes to the first and no to the second, then the rear AWD clutch packs probably need to be replaced. Some people have gotten by with trying to put an additive in there, but I don't have any experience with that.

 

Seeing that inserting the fuse in the FWD fuse holder causes the torque bind to go away, that would indicate that the duty c solenoid is functioning properly and the problem is with the clutch packs.

[Twitch de la Brat]

OK, well the torque bind goes away when the FWD fuse is put in, as far as I

know, I have yet to drive the car extensively since putting the fuse in.

 

But the vibration remains.

I personally have only been able to get it to vibrate while turning once, all the

other times it was my sister referring information to me.

So it seems to be intermittent.

I'm going to be inspecting it in a little more detail when I can get the car.

 

I fear I may need to install a new tranny.

 

Twitch

 

PS: All of the testing I have been doing has been with the FWD Fuse in.

[ericem]

Try and find this Trans-x stuff.

 

http://www.amazon.com/Products-Trans-X-Automatic-Transmission-Steering/dp/B00030BFFG

[johnceggleston]

based on your description of the fluid, i bet your transfer clutch plates are all gummed up. clean fluid (full flush or several drain and refills) and driving time may 'clean' them up some / enough, but replacing them will be a sure fix. (the clutch does not engage the plates when the FWD fuse is installed, i think)

 

the only question in my mind would be, given the labor to pull the transfer housing and the cost of the plates ONLINE, do you spend the extra $75 - $85 for the duty c?

 

or as mentioned do you just swap in another trans?

 

and if you do swap in a used trans do you address the transfer clutch before install?

 

sorry, more questions than answers.

 

i guess the vibration could be an axle??

[Twitch de la Brat]

Try and find this Trans-x stuff.

 

http://www.amazon.com/Products-Trans-X-Automatic-Transmission-Steering/dp/B00030BFFG

 

I've tried that stuff in the past, and it has only really helped hard shifting and the occasional gear stall (not going when you want it to)

 

based on your description of the fluid, i bet your transfer clutch plates are all gummed up. clean fluid (full flush or several drain and refills) and driving time may 'clean' them up some / enough, but replacing them will be a sure fix. (the clutch does not engage the plates when the FWD fuse is installed, i think)

 

the only question in my mind would be, given the labor to pull the transfer housing and the cost of the plates ONLINE, do you spend the extra $75 - $85 for the duty c?

 

or as mentioned do you just swap in another trans?

 

and if you do swap in a used trans do you address the transfer clutch before install?

 

sorry, more questions than answers.

 

i guess the vibration could be an axle??

 

Well, with the new fluid, the torque bind diminished somewhat.

And if it is the clutch packs, I'm just going to swap in a new transmission, its

not worth it to pay a few hundred dollars for new clutch packs, when I could

get a decent used tranny that's warranteed for 6 months for almost half

price.

 

And I'm pretty sure its the torque converter not slipping smoothly, but I need

to do more testing with the car, when I get the time.

 

Twitch

 

PS: And there is NO torque bind with the fuse installed, we cannot get the

back tires to tear up gravel with the FWD fuse in.

[johnceggleston]

And I'm pretty sure its the torque converter not slipping smoothly, but I need

to do more testing with the car, when I get the time.

 

Twitch

 

PS: And there is NO torque bind with the fuse installed, we cannot get the

back tires to tear up gravel with the FWD fuse in.

 

the torque converter has nothing to do with toeque bind, i don't know if it can cause vibrations.

 

if the new fluid helped the torque bind some, then change it again and drive it, it may improve some more. you need to clean out the gunk. driving the car on the hiway with torque bind will do minimal damage to the drive line and may help clean up the clutch plates.

 

if your solution is to swap the trans, you have nothing to lose except the cost of the fluid.

[Twitch de la Brat]

the torque converter has nothing to do with toeque bind, i don't know if it can cause vibrations.

 

if the new fluid helped the torque bind some, then change it again and drive it, it may improve some more. you need to clean out the gunk. driving the car on the hiway with torque bind will do minimal damage to the drive line and may help clean up the clutch plates.

 

if your solution is to swap the trans, you have nothing to lose except the cost of the fluid.

 

Ok, I'll try having her take the fuse out and drive it like that for a while.

We just put in cheapo walmart tranny fluid until we can get the problems

worked out.

 

If it makes the torque bind go away then awesome, if not, then I guess I'm

just going to have to find her a new tranny.

 

Now for the vibration, I'm still hunting that problem down.

I'm going to check out the axles hopefully tomorrow.

But, I'm almost positive that its not the axles, but being an intermittent

problem, it may point even more towards the axles since the problems with

them tend to be under specific conditions.

 

Twitch

[Legacy777]

Yeah I wouldn't rule out axles. I had a pretty harsh intermittant vibration that was axle related.

[Gloyale]

And if it is the clutch packs, I'm just going to swap in a new transmission, its

not worth it to pay a few hundred dollars for new clutch packs, when I could

get a decent used tranny that's warranteed for 6 months for almost half

price

 

I totally disagree.

 

Clutches for just the transfer gear are less than $175 bucks for all the plates and a proper adjusting shim, from Subaru. Other places they are even cheaper.

 

The trans doesn't even have to come out to replacve them.

 

With all the threads about torque bind in 4EATs (hundreds it seems) you are really taking a crap shoot with a used trans.

 

Now if it didn't shift right, or free revved in 3rd gear or something(also common), then yeah get a used one.

 

But the transfer clutches are SOOOO easy to replace, in the car even, that you are far better off to install new clutches.

 

Don't forget to grind the notches off the transfer hub before installing the new clutches.

 

The fact that your FWD fuse works to disengage the rear is a good sign, means the TCU is working, and the Duty C solenoid is good, so it must be the clutches. Heck you may even solve it by simply grinding off the notches of the hub and not even need new clutches(but I'd replace them anyway)

Edited April 1, 2010 by Gloyale

[Twitch de la Brat]

I totally disagree.

 

Clutches for just the transfer gear are less than $175 bucks for all the plates and a proper adjusting shim, from Subaru. Other places they are even cheaper.

 

The trans doesn't even have to come out to replacve them.

 

With all the threads about torque bind in 4EATs (hundreds it seems) you are really taking a crap shoot with a used trans.

 

Now if it didn't shift right, or free revved in 3rd gear or something(also common), then yeah get a used one.

 

But the transfer clutches are SOOOO easy to replace, in the car even, that you are far better off to install new clutches.

 

Don't forget to grind the notches off the transfer hub before installing the new clutches.

 

The fact that your FWD fuse works to disengage the rear is a good sign, means the TCU is working, and the Duty C solenoid is good, so it must be the clutches. Heck you may even solve it by simply grinding off the notches of the hub and not even need new clutches(but I'd replace them anyway)

 

OK, the quotes I've been getting from shops have been a good chunk more, as in $400-$500 just for them to get the plates

 

And as for replacing the plates, yeah, I could do it with the car just on blocks

and in a few hours, I've seen how easy it is to pull the rear housing.

And the plates just slide out, so even easier.

 

And if the torque bind is just caused by gunk in the plates, would trans-tune

by seafoam work for cleaning it out?

I've never used it before, so I just want to know if somebody has used it and

if it is a cleaner, or just a conditioner like the rest of them.

 

Twitch

[Twitch de la Brat]

Well, we've got some trans tune in the tranny, cleaning out the clutch plates,

but we still get torque bind WITHOUT the FWD fuse.

With the fuse there still is the occasional shudder when cornering, but its

been mostly wet around here, so not much dry pavement testing as of late.

 

New question, will the duty C solenoid out of an XT6 4EAT match up?

I'm pretty sure it will, but I think the output shafts are different?

I've done a fair amount of searching (couple pages) and didn't come up with solenoid swappability.

 

I know the TCU's will swap, but I've got a spare one of those sitting around,

in case it needs swapping.

 

So, anybody have any experience in this?

 

Twitch

[mdjdc]

Pull the extension housing, grind the notches off the hub that the clutches go on and I will bet you will be golden. I have done several of these and the fix was immediate. Got the fix right here on the board.

[coldfusion21]

Can someone expand on the notching?

 

Getting ready to change transfer clutch assembly on a 1990 legacy. No torque bind that I recognize. On gravel or snow I seem to have fwd only. Sounds like the duty c solenoid might be a good idea while I'm in there?

 

Thanks for all the help.

[mdjdc]

I am betting that the car had torque bind for so long that the shaft that houses the clutches has had the drum shear off of it and it is spinning freely now. That would be why you have FWD only now. I had a car that I bought and when I tore into the tranny, that is what I found.

[wtdash]

Read thru this POST about fixing torque bind/delayed AWD engagement. I had that issue on my '90 and used the info in the post to fix it.

 

It shows/explains how to file down the notches/grooves so they don't cause the issue anymore.

 

Notches (page 3 & 6 of the POST shows a "how to"):

 

td

Edited November 21, 2011 by wtdash