Removing Auto trans from 4.4, couple of questions

[TriX5]

Ok, I am ready to torq up the valve body I guess.

Question, do I have to remove the output shaft to replace the rear oil seal?

I just found that I ignored one instruction in putting the oil pump together. The teeth apparently have to engage just so... Luckily I had not torqed it yet.

[RRPhil]

Regarding the lip seal on the output shaft, I believe that the ‘029’ model of the 5HP24 (fitted in the E53) has a separate splined shaft to extend the rear epicyclic carrier output shaft to the transfer box, doesn’t it? On the Range Rover (with which I’m much more familiar) this extension shaft isn’t used and instead the carrier assembly is a different part with a longer shaft



This means that the rear lip seal is different for the Range Rover whereas the E53 transmission uses the ‘standard’ seal provided in the overhaul kit. Is the extension shaft just held in the rear cover with a circlip or something? I’d be interested to see some photos if you get chance - if it isn’t too late. I guess you should replace the seal while access is relatively easy?

With the oil pump it is important that the indentation in both the internal & external gears faces the same way up.

Phil

[TriX5]

Hi Phil,

Yes, I made sure the pump went back together the way it came apart. I just didn't line up the dots like in the manual. So last night I made the small correction.

The manual shows the output shaft with a slotted nut but mine is held in by a circlip. I think it should be easy to remove. I will take a picture.

[TriX5]

Here is a picture, the bearing had play on it and now after some hammering to get it out it is simply dead.

Sorry, second picture is out of focus, tomorrow I'll get a better one.

[GT3Jeff]

Excellent thread TriX5, and a impressive piece of work you are taking on. Nice. Also, thanks for posting to my Sway Bar thread.

A couple questions for you about the AT removal:
- Did you remove the top AT bolts from above behind the topside of the engine at the firewall, or did you remove the transfer case and get at them from under the vehicle?
- What did you decide to do for replacement fluid? This one scares me a bit. It seems to be crucial to have the right fluid for the AT to survive. I thinking of getting the fluid from the dealer, but the cost is CDN$340 for 9 liters.

Thanks again.

[TriX5]

Top bolts I did from the top, I wanted to take the AT/TC out in one piece. I have the top side apart for the V-pan replacement anyway.
I got fluid from the dealer at 20% off. Some people found a Mobil1 product I believe that meets the spec.

THis has been a long project coz work and other stuff around the house has been getting in the way but it is not very hard with the right tools. Getting the AT off the car is the hardets part IMO.

Good luck.

[civdiv99]

Not meaning to swing thread off-course, but I'd be curious if there are any verified failures of this tranny specifically linked to or caused by using a substitute fluid. I have used the Mobile 1 synthetic multi-veh ATF in my X5 since trans rebuild last summer which includes stop and go commute driving, cold winter mornings, and on 2 occasions 80 mph trips for a couple hundred miles at a stretch. Interestingly, this trans model was out and about before this "LT" lifetime fluid was called for, and the trans was not considered lifetime fill. Anyway, looking at one of the $20 something per qt bottles of the BMW called-for stuff, I noticed on the back of the label that it was manufactured by Mobil anyway. Since I have no qualms about using the Mobile product, I'll certainly be continuing its use and will duly inform the group should I think anything is amiss.

Other thing I did was completely bypass the factory trans cooler (blasphemy!, how dare I). A B&M Supercooler #70273 fits behind the front fan assy perfectly (open yer hood and take a look, you'll see the gap behind the front fan on either side). Is not really visible as installed, and the hottest I've been able to get the pan (nothing hi-tech - IR thermometer on the pan) is around 155, and that day I was really trying to heat it up on purpose to see what I could get - full throttle runs up hills, keeping rpm up, etc.

Only reason I did the bypass is - 'cause I just didn't like the stock one, and under there one day with the splash pan off, I was rather surprised at how HOT the little block cooler was under there. I just wish I would have measured and documented the original temp. Curious to know how hot the stock cooler allows the fluid to get.

[JCL]

I don't recall seeing any full failures documented here, but this board is a pretty small sample. I have seen posts here and elsewhere documenting shifting problems when an incorrect fluid was installed, and that was rectified by installing the correct fluid. All anecdotal.

The most common problem with incorrect fluid (from my experience on other transmissions) is the friction characteristics not being correct, thus causing poor shifts. All decent transmission fluids will lubricate, some will last longer than others, but the big difference between different fluid specs is the friction spec as the clutches engage. Manufacturers achieve those specific friction characteristics with friction modifier additives. Those additives are sometimes sold separately, to resolve borderline shifting problems.

Just curious as to when you installed your aftermarket cooler, you thought about the heating circuit. Usually the thermostat has a bypass that uses the heat exchanger to heat up the automatic transmission fluid upon cold start, thus reducing transmission wear. Have you maintained that function? I don't know what the long term effects are of eliminating the heater function, but perhaps you don't experience any cold starts. On other models where BMW adds a second transmission cooler, they maintain the standard cooler just for the heating function, and add a second cooler for additional capacity.

[civdiv99]

I considered putting the orig cooler back in the circuit. But then coldest morning for a startup and drive after cleaning windows, etc. was 7 below zero (F) with the Mobile fluid and my experimental trans cooler. No issues that I noticed, so I'll stay where it is for now.

[TriX5]

The more I read about this problem, the more I think that one failure mode maybe that some cars get the torque converter replaced but the AT goes back on without cleaning up. Then sometime down the road it starts having problems as the metal shavings start circulating through the AT giving trouble with the valve block and pump. (And dealers/shops are being told you should not swap the fluid, then they will be hesitant to flush). Faced with another x-thousand dollar R&R bill, the owner gives up and shoves the car in to the trade where some hapless buyer picks it up unaware it is a timebomb.

The reason I am saying this is that I cleaned out my valve block with solvent in a white container and yesterday I put the used solvent in a bottle for disposal. The crud that remained on the bottom of that container after pouring out the solvent contained a very significant amount of shavings, though not of the size RRPhil's picture shows. Now clearly the majority of this is stuck to the outside of the valve blocks but as you can see from Phil's pictures some of it finds its way in as well.

Once the damage is done all the fllushing in the world is not going to fix it until the AT gets rebuilt, and even then some damage to the valve blocks maybe overlooked or somebody takes a short cut and does not actually rebuild the valve bloock and the AT goes back on still with problems.... Any thoughts on this?

CivDiv did you get the Mobil with the LT spec or did you use the generic? Mobil does not show that spec on their website and I was going to check in the store but would be interesting to know what you put in?