2001 4.4 replacement trans, no reverse? Update, Fixed and driving!
 

I picked up a 2001 X5 a couple months ago with a bad trans, looked like the infamous "A" clutch failure (http://www.xoutpost.com/bmw-sav-foru...x5-issues.html), found a used trans from a running and driving 2001 X5 and picked it up. Today, I finally got around to buttoning it all up, get it started up and it seems forward gears are perfectly fine, but absolutely nothing in reverse. It is still up on jack stands so there is not even any resistance at all on the wheels to spin but still nothing at all in reverse, I would think that even if the trans did have the F clutch piston seal failure that being up in the air I would get at least some movement, but I get nothing at all.

I can't seem to find my scanner right now, ordering a bluetooth scanner off Amazon tonight, so until then I can't even check to see if there are any codes.

Is there any other failures that could cause this that would leave the transmission with no movement at all in reverse?

Just found this, ZF Tips with a European Flavor - Sonnax

I will check out the wiring tomorrow after work.

Unless you have the App Icarly, I don't think a generic bluetooth scanner will be able to read the TCU / EGS module. Do you see the R in the dash display when the shift lever is in the R position?

Yes, dash displays R, reverse lights also come on. I am thinking that this means the switch is operating correctly, going to check it anyway as its a quick check.

Did you verify that the used transmission was in perfect working order prior to obtaining? Because if you didn't its just a roll of the dice.:yikes:

I was assured it worked, from a very reputable shop in a good area known for working on BMWs, got the trans for much cheaper then most I have seen though. If it turns out to be an internal failure I will surely contact them. I definitely agree on a roll of the dice with a used trans, but for the price vs time to rip into mine and fix it I just wanted a quick in and out swap. The plan was to rebuild the original and have it ready to swap back in if there was a failure or find another X5 with a bad trans and pick it up to swap in. The good news though is now at least if I have to take it back out again I can have it done in less then a day.

If you check the transmission serial number on the green plate on the LH side of the maincase, if the number is higher than 0424941 (i.e. a build date after 29th August 2001) then the transmission has the latest, upgraded, F-clutch piston. I’ve never yet seen one of these fail.

What the Sonnax article is saying is that if you disconnect the 16-pin plug at the back of the transmission you can deliberately put the transmission into failsafe mode.

http://i260.photobucket.com/albums/i...pscxxgfsya.jpg

Failsafe mode provides a direct hydraulic path in reverse, via the manual valve, to the C & F clutches without risking any intervention from the MV3 solenoid or the reverse gear protection valve (RG-V).

http://i260.photobucket.com/albums/i...08/RG-VMV3.jpg

If the transmission will then reverse, you have an electrical/electronic fault rather than a hydraulic/mechanical one.

Phil

Thank you Phil, I have read countless posts on these transmissions with your input and it really shows you know what you're talking about, I was hoping you would jump in!

Have you ever known one to be so bad of a failure that even up on jack stands with all four wheels off the ground there is still no reverse?

I agree that you would expect a small amount of clutch drag, and hence torque on the output, even if a seal was leaking or there was a mechanical issue. Maybe it does indicate that reverse isn’t even being signalled to engage (valve body assembly issue?). Anyway, best to carry out the test.

Phil

Disconnected the harness, still no reverse, sadly just like I expected.

The engine seems to have a load on it when in reverse, you can hear it drop in RPM slightly like it normally would so I know there is something going on in there. Hoping to get this nailed down before the weekend, if it needs to come back out I want to have it out and ready to go back in by the end of the weekend.... if I have time haha!

Did the replacement trans come with everything, or did you have to use some parts from your old trans like the valve body?

Everything included, bolt in, plug in and go.

Strange that both trans don't have reverse. How your transfer case?

Transfer case seemed just fine, old trans had reverse without issue just when warmed up would go trans failsafe and default to 5th gear.

Called the shop owner yesterday to ask about the trans and verify it had reverse, he said 100% it had reverse without issue, he hauled a trailer with it and backed the trailer into his shop with it. He offered another transmission if this one is actually bad.

At this point I feel like there has to be something else at play here, I just can't make any sense at all of no wheel movement in reverse even freewheeling on jack stands. When I put it in reverse you can tell there is a load being out on the engine, I know something is happening but still no movement. Doesn't matter if I go for reverse immediately after I start it, or let it get warm then try, or leave it in reverse for a couple minutes or rev the engine up, still nothing. I have rebuilt automatic transmissions before and seen some very fried clutches and even that bad the trans would still move when cold or at least attempt to, enough to move the wheels in the air on stands for sure.

So help me to understand here. The vehicle has drive (wheels move forward with X5 jacked up in the air) but no reverse. If this is the case I would suspect that there is something internally wrong with the transmission and not the transfer case. Have you tried jacking the vehicle down and check it on pavement instead of in the air? Try the simple things first

Exactly, no reverse even up in the air but forward gears are fine. Definitely not a transfer case issue, no way possible I could even see a transfer case working in drive but not reverse, and yes, splines on the front driveshaft are in very good shape.

I'm not going to drop it to the ground until I figure out what the problem is, I can see no way that being on the suspension could lead to loss of reverse... though I have heard of dumber things...

Really just not sure what to think at this point, I think I'm going to drain it and inspect the valve body.

Almost sounds like the park lock is still engaged – though I can’t see how that could happen because the rooster comb controls both the park lock and the manual valve. The wheels do freewheel when reverse is selected and aren’t locked solid?

Phil

Maybe kind of a stupid question: but maybe your selector lever is not adjusted the right way?

No stupid questions at all here, I'm grasping at straws myself as to why it's happening. At this point I believe I will end up pulling the trans because I can't make any sense of anything else. I disconnected the electrical to all the solenoids, which should be a direct path then to reverse and still no change.

As for wheels freewheeling in reverse, I can go from drive at idle speed with the wheels still rolling and brake just enough to allow it to go into reverse without stopping the wheels and the wheels still freely spin forward until the lack of power being applied to them stops them. Yes... I know it's not a good idea to go from drive to reverse, of course it can cause damage, at this point I'm not really worried about an idle speed drive to reverse drop with no load, was more curious to see if there was any resistance and there was not.

And you mentioned that when you put it in gear for Reverse you can hear the load against the engine correct? Then I am inclined to believe that the problem lies in the Transmission after all you have drive.

There is absolutely no doubt that the problem lies in the transmission, I never suspected anything else other then maybe a fault code which wouldn't matter. The question is where in the transmission does the problem lie, I am hoping it is something I can fix without dropping the trans and pulling it apart to find a destroyed F clutch piston, though I feel that is where this is headed.

Just remembered something.

When I pulled the transfer case off the input shaft for the transfer case came halfway out of the case. I was able to get it back in place as far as I could tell, any chance something happened when that shaft came out that could cause the issue?

Finally an update here! :rofl:

I've been quite busy with work and family time, don't need the X5 until snow anyway so it's been on the back burner a bit. Finally had some time to dig into it again these last few days, I started to pull the valve body and did some more research and figured it was just a waste of time and decided to pull the whole trans. This time I had it out and on the bench in about three hours :thumbup:

Tearing it open was pretty straight forward, I have rebuilt around a dozen GM automatic transmissions so this wasn't all to unfamiliar. From some other posts / pictures on here it seems like this trans has been apart and at least partially rebuilt before, the A clutch drum assembly has the dimples that from what I understand is an updated part and was put in the newer transmissions built after this one. In any case, this A clutch assembly looks like new. The radial bearing that typically fails also looks excellent with no visible pitting or wear. Of course I found the smoking gun in the F clutch piston, completely destroyed.

Dimples on A clutch hub
http://i152.photobucket.com/albums/s...pssc8s6ld9.jpg

Snap ring groove and the rest of the drum looks excellent with no cracking or wear.
http://i152.photobucket.com/albums/s...psxf0jnw3h.jpg

Radial bearing in great shape
http://i152.photobucket.com/albums/s...psbe4mqhlr.jpg

And of course the F clutch piston.... smoked. Only maybe 25% of the outer seal was in good shape with the rest of it completely gone, and the big chunk ripped out of the inner seal as well.
http://i152.photobucket.com/albums/s...psrw4jloao.jpg

http://i152.photobucket.com/albums/s...ps7xp8m1r1.jpg

http://i152.photobucket.com/albums/s...ps9encbjxm.jpg

http://i152.photobucket.com/albums/s...psz6pfthzy.jpg

http://i152.photobucket.com/albums/s...psfhuelvda.jpg


So... this is the plan. I am going to take the good A clutch hub assembly and install that in the original trans after I take that apart and make sure there is no damage to the F clutch piston in that one. It had reverse just fine but I would hate to be right there and not look at it then throw it together and have reverse go out in three months. Once I get that transmission in and all together and get the X5 on the road I will then fully rebuild the used trans that I purchased and used for parts.

Good Thread! :) I imagine then that you didn't have the updated piston ?

Nope, at least not originally by the serial number and if it did get it during a past rebuild it has failed.

Thanks for coming back and updating this post. I would send a picture of the F clutch piston to the seller and explain to him that there's no way that the transmission he sold you had a working reverse. See if he is willing to reimburse you for some of the cost such as a rebuild kit for the trans.

Well at least you know that you were not going crazy and something minor was overlooked on the the install. Once again it is apparent that when we source a used transmission anything is game on what might be wrong on the inside. I have been there before so you are not the first to encounter such an outcome.

Here's a link to a ZF5hp24 teardown trans by RRPhil (he has another user name on this forum but on thread #11 he identifies himself as RRPhil).

ZF 5HP24 teardown

If it was my truck I would just rebuild the trans with the bad F clutch piston. At least you know what was the problem and a new F clutch piston and new reverse clutches and plates should get you reverse. You said that the trans have updated parts in it already. Plus the trans is already apart

You original trans goes into limp mode once it gets warm so you are assuming it's the A clutch assembly. Could be the A clutch assembly, but it could also be something else. Until you disassemble and inspect the original trans you don't know why it goes into limp mode.

Just my .02 cent.

More work done!

I reassembled the trans I had installed and taken apart, we will call this one trans #2, with the original trans being trans #1. I wanted to get all the pieces back together in #2 before I started on anything else and got pieces mixed up.

The reassembly went pretty well, it was a little tricky for some parts but not too terrible. Upon further inspection of this transmission though, I found out that I was wrong in my earlier post stating that the radial bearing that is prone to failure was ok, I was looking at the completely wrong bearing. After looking at the actual bearing that goes bad, this one had some pitting as well and won't be good to reuse, a new one will be ordered.

Once I had transmission #2 reassembled I drained Trans #1 and started disassembly, didn't get too far though and it was time to come in for dinner and take the boys to scouts.

Transmission #2, you can see that once I actually look at the right bearing it is in fact junk :rofl: This trans had forward gears without issue but no reverse and I found the cause with the trashed F clutch piston in my previous posts.
http://i152.photobucket.com/albums/s...psvpjln5an.jpg

http://i152.photobucket.com/albums/s...ps4y6hlai0.jpg



On to Transmission #1! This was the transmission that was in it when I bought it, it would lose forward gears defaulting to 5th once warm which after much research led me to believe that the same radial bearing had failed allowing the hubs to move too much and split the O ring on the back of the hub. Bingo!!!

Clearly, the bearing had some major failure.
http://i152.photobucket.com/albums/s...psoevspmog.jpg

Approximately 1/3 of the rollers were missing and the rest were severely pitted.
http://i152.photobucket.com/albums/s...psersanruj.jpg

Lots of rubbing going on here as a result of too much movement from the bad bearing.
http://i152.photobucket.com/albums/s...psyrjexo0j.jpg

Fantastic! I found some of the missing rollers :thumbup:
http://i152.photobucket.com/albums/s...pskjqeaomg.jpg

More rubbing!
http://i152.photobucket.com/albums/s...psdal4mqib.jpg

And of course we wouldn't be complete without a ripped O ring.
http://i152.photobucket.com/albums/s...pscyk7vidh.jpg

http://i152.photobucket.com/albums/s...psyjm3i2bc.jpg



Another thing I realized after looking into it further, RPhil had posted that after xxxxxx serial number these transmissions came with the updated better A clutch drum. Transmission #2 does in fact have the updated clutch drum as the serial number shows it was built after they were factory installed, not because it has been rebuilt and the updated drum installed. Along those same lines though, it does seem that transmission #1 does have the aftermarket heavy duty A clutch drum, at least it seems that way anyway from the pictures I have seen.
http://i152.photobucket.com/albums/s...pssj5ou3o7.jpg

The drum on top is what I believe to be the aftermarket HD piece from transmission #1, the drum on bottom is the updated drum from transmission #2 which I now believe was factory installed due to the serial number.

If I am correct in my thoughts on this, is there any long term durability advantage to either drum?

As you can clearly see, the A drum from trans 1 is a lot beefier. This design was used to address the issue of the drum cracking at the snap ring. The drum from trans 2 may be an updated drum, but it is still designed based on the design of the original drum. What was change was probably the thickness of metal where the snap ring sits in. If it was my truck, I would use the beefier A drum from trans 1. Now that you know what caused the trans 1 to go into limp mode (bad roller bearing as well as broken o-ring, I would just rebuild that trans and use that for the X. After all nothing like having matching numbers for all components.

Here's a video on the updated A drum sold by Cascade Trans.

https://www.youtube.com/watch?v=7M9pgm4cgE0

You should also install a new pressure regulator valve if that is the reason for why the original A drum was replaced.

Here's a video on what to replace after an A drum failure.

https://www.youtube.com/watch?v=UpG91-ZzYY8

Is that a crack on the input shaft ?

No crack on the input shaft, just the way the light is shining on it, thanks for point that out though as I would have missed it if it was!

I will be using the HD drum for this transmission. I finished the teardown last night and everything else looks perfect, the F piston looks brand new so I was happy about that. I ordered the bearing from Cascade Transmission last night and have received notification from them that they are out of stock and it will be another week or so before they get some in, I may have to cancel and source one somewhere else as I do not wish to be under this thing in below freezing temperatures putting it all back together.

I do very occasionally see 5HP24 A-clutch drum failures, even with the new stiffened drum and the ‘10mm’ main pressure relief valve fitted, but these are quite rare so I personally don’t resort to fitting aftermarket drums like the one in your photo.

http://i260.photobucket.com/albums/i...psxcqa552b.jpg

http://i260.photobucket.com/albums/i...psod5bf3q6.jpg

http://i260.photobucket.com/albums/i...psnw1hirxh.jpg

It’s important to separate the cage from the raceway of each axial needle roller bearing (use something plastic to prise the cage off – and it only fits back again one way) to check that the raceway isn’t spalling underneath, where otherwise you wouldn’t see it.

http://i260.photobucket.com/albums/i...08/raceway.jpg

I’d also strongly recommend that you check the input shaft endfloat following the rebuild (should be between 0.2 & 0.4mm), fitting a thicker shim if necessary, as the B clutch hub often wears underneath the bearing race.

http://i260.photobucket.com/albums/i...Racelifted.jpg

http://i260.photobucket.com/albums/i.../02260shim.jpg

http://i260.photobucket.com/albums/i...psnjffhokc.jpg

Phil

Try Ericksson Industries.

Eriksson Industries

Well, time for an update here.

To make a long story short, the guy that sold me the transmission flat out ripped me off, no way around it. He repeatedly told me time after time that it was tested, verified as working good, but the story changed many times as to how it was tested and who tested it. I asked for a partial refund of $350 and was offered $250 which I felt was an insult and stuck to my guns. I was ignored for two weeks, posted the whole story in the Michigan BMW group on facebook and it blew up spreading to several other groups where I found out that this kid has a TERRIBLE reputation for ripping people off, running his mouth, and just in general being a giant douche bag. I ended up getting no refund at all because I refused to take down the post and my review on his shop, I don't want anyone else to ever get ripped off like I did, if I can save someone else some money and wasted time it's worth it to me. Metro Motors in Mt. Clemens Michigan is the shop you want to avoid like the plague!

SO... with that out of the way, I ordered the bearing from Cascade transmission as stated above and when it finally got in stock they shipped it out and it got lost in the mail for almost a week. The bearing arrived at my house a couple days ago and it has been far too cold and I have been far too busy to work on assembling it. The time will come, but right now I have a lot to do so it will wait and the 540i will continue to do winter duty.

http://i152.photobucket.com/albums/s...psy8kihlmq.jpg

Thanks for all the picks and info! Great thread! You gotta hate the rip-off part though, that kinda thing drives me nuts! Good for you for posting the heads up ;)

I have had the transmission all reassembled for several weeks now but finally with the nice weather here in Michigan this last weekend I was able to get it all back together. I have roughly 150 miles so far on the rebuild and I can tell you that this is very quickly becoming one of my favorite vehicles that I have ever owned! It very much reminds me of the power and handling of my 540i but in a package like our Acadia yet much more nimble.

Great job!!

I couldn't agree with you more!! I got my 4.6is with a bad front drive shaft (aftermarket jobber with the extended splines; that failed without damaging the TC splines!! Goes to show the upgrades aren't worth it sometimes)... I used the original TC and a used OEM front driveshaft... Made sure the splines were greased and the dust cap was secure and made a good seal... After driving it a week, it quickly replaced my life long love (2001 540i/6) despite the X having the automatic trans...

Again!! Very nice job and thanks so much for sharing!!

Cheers!!