4EAT Tranny Clunk in Reverse and 1st

[NorthWet]

I have a problem with a new-to-me 92 SVX. The tranny is misbehaving (DUH!... SVX!), with major clunking when selecting Reverse or 1st.

 

BACKGROUND:

Our 3rd 92 came to us inexpensively, as the PO tried to do some work on it, and somewheres in the process broke the ignition key off in it. He then tore apart the ignition lock/switch assembly with vice grips and a hammer. Not getting the quality of results that he had expected (i.e. broken key removed from lock, lock reassembled in pristine working order) he let it sit for a year or so. Relatives were tired of it sitting in their driveway, and got his permission to sell it. Advertised as "bad torque converter"...

 

I have resolved the ignition (even rekeying to original code), and finally get to check out the mechanicals. Engine started up with first turn of the key and settled into a beautiful idle. (Kind of surprised, because when the trunk was opened I found a seized waterpump... so the guy had a chance to mess up the t-belt alignment and make a little more work for me.)

 

OK, so on to the

 

PROBLEM:

Tranny fluid looks bad but not as bad as the mud that came out of our 2nd 92. While sitting still, tranny engages roughly in Reverse and First (manually), producing a car shaking clunk. No such clunk is felt/heard shifting out of those gears or into any other gear; Drive, Third, and Second produce no sensation when selected.

 

When moving, Fourth does not seem to get engaged, and I do not think Third does either. I do think that I feel an upshift, which I am assuming is 1st-2nd (but might be 2nd-3rd). My roadtesting so far has been limited for various reasons.

 

So... obviously one of the things that is needed is a fluid flush. The "when" is the question, based on what is likely causing my clunking and no high gears.

 

I assume the clunking is caused by rough engagement of the band. If so, is this likely due to sticking actuator piston or to excessive clearance of the band? If I need to adjust the clearance (not a fun task when your "shop" is a crushed rock driveway) I would probably wait to do the flush until after draining and lowering the tranny. If probably just sticky internals, I would flush and probably throw in a flush additive.

 

Long story short: Should I flush first and reevaluate, or bark my knuckles and lacerate my back to adjust the band? Or am I way off as to the problem?

 

(This is cross-posted from "'www.subaru-svx.net", where I have gotten some looks but no posts.)

[four-fleet-feet]

...he let it sit for a year or so

Considering that part of your quote, I'd try the flush and additive first. But that's me - since I know it was a wet winter in WA this year. If the driver was so, well, inane to pull apart an ignition the way you describe, I'll bet he also didn't do basic maintenance. After a year without fluid circulation (even dirty fluid) I'd be a little cranky, too. However, if the clunk is that bad, I suspect there's another problem caused by lack of care. You never know; what can the flush hurt? OK, you'll waste fluid if you have to drop it later, but at least it'll be a cleaner job to spot problems.

 

Besides, if the fluid helps, you're on the road. If not, at least you can eliminate that from the list of maybes!

 

Anything to avoid the late-summer Washington get-under-car. I have a dirt driveway - mud! Yum! NOT.

[nipper]

Flush first. If flush has no effect, then you have a deeper issues.

 

The clunk may also be as simple as a bad tranny mount, or if this is AWD a bad universal joint.

 

 

Dont adjust the brake band, as you need an inch-lb torque wrench to do it properly, and with the typical svx tranny issues, will not have any effect. The brake band would not have any effect on 4th gear, which may be the begining of the end.

 

In any case, you will need to add a aftermarket cooler and tranny filter to avoid the SVX curse.A temp gauge would be a good idea too.

 

 

good luck.

 

nipper

[usaru]

The clunk may also be as simple as a bad tranny mount, or if this is AWD a bad universal joint.

 

I had a loud clunk when shifting into !st or R, it also sounded when coming to a stop. Loose axle nut diagnosed during inspection. 3 seconds with an air gun fixed it (for free, although I did throw the mech a tip). I could hear my wallet and back breath sighs of relief.

 

Hope you get lucky.

[NorthWet]

Flush first. If flush has no effect, then you have a deeper issues.

 

The clunk may also be as simple as a bad tranny mount, or if this is AWD a bad universal joint...

The clunk is very strong and specific, only occurring when the selector is moved into reverse or into first. No clunk selecting out of those gears, no clunk when selecting D/3/2. General "feel" is that the clunk is down by my ankles or shin area. Fairly certain it is not primarily a mount or a u-joint.

 

...Dont adjust the brake band, as you need an inch-lb torque wrench to do it properly, and with the typical svx tranny issues, will not have any effect. The brake band would not have any effect on 4th gear, which may be the begining of the end...

I do have an inch-lb torque wrench. My experiences with other 4EATs is that the an inoperative band will restrict the tranny to reverse and first, so by extension a misbehaving band might also.

 

Still, not at the top of my fun-to-do list.

 

...In any case, you will need to add a aftermarket cooler and tranny filter to avoid the SVX curse.A temp gauge would be a good idea too.

 

 

good luck.

 

nipper

I need to find someplace that will give a volume discount on filters and coolers. Still need to add these to my wife's 92 before it starts exhibiting problems, and might as well add them to her Legacy.

 

Thanks for the input.

[nipper]

The band doesnt help the 3-4 shift, and usually thats where the doom and gloom starts.

 

get a case of filters thats a 6 year supply

 

nipper

[Turbone]

Theres been lots of discussion on the SVX board on whether the flush is a good idea or not, It could loosen some debris and clog the internals, etc.

What is a good idea is to change the filter and replace the fluids.

Also check to see if it has the in-line filter. Its down on the left frame rail by the wheel well. Its a replaceable item.

Mine also has a bad clunk when you put it in reverse only. And it only does it when cold. I thought it might be a tranny mount, but I havent had time to crawl under and check

And theres been some discussion about a tranny cooler for us in the PNW. Some say it isnt necessary because of cooler temps.

I installed one anyway.

[nipper]

Theres been lots of discussion on the SVX board on whether the flush is a good idea or not, It could loosen some debris and clog the internals, etc.

What is a good idea is to change the filter and replace the fluids.

Also check to see if it has the in-line filter. Its down on the left frame rail by the wheel well. Its a replaceable item.

Mine also has a bad clunk when you put it in reverse only. And it only does it when cold. I thought it might be a tranny mount, but I havent had time to crawl under and check

And theres been some discussion about a tranny cooler for us in the PNW. Some say it isnt necessary because of cooler temps.

I installed one anyway.

 

The problem with the ransmission has nothing to do with air temp or age of the fluid. The transmssion sheds material off the lock up torque converter clutch. This material clogs the transmission and the small pathways of the internal tranny cooler. By adding an aftermarket cooler you have a larger tube to cool the tranny fluid.

 

New fluid was a valid argument back in the 1970's, but not in the 1990's or newer.

 

nipper

[NorthWet]

Yeah, this has the standard inline tranny filter. My gut feeling on this is that the servo piston for the band is sticking and releasing... it has that overall "quality" about it. My gut is less "calibrated" as to whether or not excessive clearance is adding to the engagement shock.

 

I had read over in SVX-land about worries about flushes, but the couple that I had read stated some "nonsense reasoning" from auto shops (e.g. - "the crud is holding the gears together"). However, the possibility of a rapid release of crud clogging passageways I can get behind.

 

Guess I will take it slow and easy for a bit, just doing drain and fill. Fluid hasn't darkened yet, just not a proper pink color. (But then, the power steering fluid looks the same color, so maybe the PO just put in some odd ATF.)

 

Nipper: Are you talking about a case of inline filters? Do you know where I can get a good deal on case lots? I was planning on getting a few spin-on mounts, probably from Summit. My wife likes automatics, so I am "blessed" with 5-6 vehicles that need filters and coolers.

 

Well, my rebuilt alternator should arrive tomorrow, along with my paycheck. So hopefully Saturday I can install the alt (getting REALLY good at SVX alt R&R), finish the registration process, and change the ATF. Then I can find out what my $250 bought me.

[Turbone]

The problem with the ransmission has nothing to do with air temp or age of the fluid. The transmssion sheds material off the lock up torque converter clutch. This material clogs the transmission and the small pathways of the internal tranny cooler. By adding an aftermarket cooler you have a larger tube to cool the tranny fluid.

 

New fluid was a valid argument back in the 1970's, but not in the 1990's or newer.

 

nipper

 

I wasnt relating his problems with the tranny cooler. I mentioned it because he said he was going to install one. And yes, it makes a difference on how the tranny operates. For it to operate correctly, the fluids need to be in a specific temp range(122deg-176deg). If its too cool, its not going to shift smoothly.

I dont understand how you think the age of the fluid wouldnt affect the operation of the tranny? Especially with a bunch of junk flaoting around in it.

I've had 4 Subaru's with the 4EAT in them and so far, 2 are garbage.

I hope to have better luck with the other 2.

Pat, I have a tech manual specifically for the 4EAT, your welcome to borrow it anytime.

[nipper]

I wasnt relating his problems with the tranny cooler. I mentioned it because he said he was going to install one. And yes, it makes a difference on how the tranny operates. For it to operate correctly, the fluids need to be in a specific temp range(122deg-176deg). If its too cool, its not going to shift smoothly.

I dont understand how you think the age of the fluid wouldnt affect the operation of the tranny? Especially with a bunch of junk flaoting around in it.

I've had 4 Subaru's with the 4EAT in them and so far, 2 are garbage.

I hope to have better luck with the other 2.

Pat, I have a tech manual specifically for the 4EAT, your welcome to borrow it anytime.

 

What i meant was that in 1990's transmissions on, its safe to change the fluid at any time.

 

nipper

[nipper]

Yeah, this has the standard inline tranny filter. My gut feeling on this is that the servo piston for the band is sticking and releasing... it has that overall "quality" about it. My gut is less "calibrated" as to whether or not excessive clearance is adding to the engagement shock.

 

I had read over in SVX-land about worries about flushes, but the couple that I had read stated some "nonsense reasoning" from auto shops (e.g. - "the crud is holding the gears together"). However, the possibility of a rapid release of crud clogging passageways I can get behind.

 

Guess I will take it slow and easy for a bit, just doing drain and fill. Fluid hasn't darkened yet, just not a proper pink color. (But then, the power steering fluid looks the same color, so maybe the PO just put in some odd ATF.)

 

Nipper: Are you talking about a case of inline filters? Do you know where I can get a good deal on case lots? I was planning on getting a few spin-on mounts, probably from Summit. My wife likes automatics, so I am "blessed" with 5-6 vehicles that need filters and coolers.

 

Well, my rebuilt alternator should arrive tomorrow, along with my paycheck. So hopefully Saturday I can install the alt (getting REALLY good at SVX alt R&R), finish the registration process, and change the ATF. Then I can find out what my $250 bought me.

My pain puter is sick, so i am on my laptop. I dont have the url, but there a subaru supplier that was getting rid of his spin-on filter kits as a close out (for the tranny). They will work with any transmission. I will see if i can find him again. He was almost giving them away.

 

nipper

[NorthWet]

My pain puter is sick, so i am on my laptop. I dont have the url, but there a subaru supplier that was getting rid of his spin-on filter kits as a close out (for the tranny). They will work with any transmission. I will see if i can find him again. He was almost giving them away.

 

nipper

Totally good! Much rather have spin ons than "one-for-a-lifetime" inline filter. (Lifetime of what? The tranny? :-\ Kind of self-fulfilling prophesy...)

 

My intent is to get decent tranny coolers. Just trying to decide if I want to go thermostatic or just plumb it before in-radiator coooler. (Latter might risk the "small passage" issue.) IIRC, if pan fluid temp is below 160F the TC won't lock up, so don't want to overcool.

 

Rob, is that 4EAT tech manual any more detailed then the FSM sections on it?

[nipper]

Just plum it in in and get a small one. Thermostatic ones are for if your always pulling trailers (bigger cooler) and live in a artic state (ND SD MI etc etc).

[NorthWet]

Just plum it in in and get a small one...

Are you recommending stand-alone or in-series/inline with the in-radiator cooler?

[Turbone]

I installed mine before the radiator(in line). Havent had any issues yet and have put some cruises on it. Its not big and it sits inside the drivers fender well, with the liner cut/vented for air flow.

The manual I have is from the AT Service Group. Its a very detailed manual for rebuilders.

[NorthWet]

I installed mine before the radiator(in line). Havent had any issues yet and have put some cruises on it. Its not big and it sits inside the drivers fender well, with the liner cut/vented for air flow.

The manual I have is from the AT Service Group. Its a very detailed manual for rebuilders.

Hmmm... I might be interested in borrowing that manual. I have this growing feeling that I might be doing some tranny rebuilds in the near future... unless a NEW New New Ecomomy occurs and I get properly employed.