Transmission Removal, 540 Auto, Fishing for ideas.

Seasons greetings,

I am about to perform a driveway transmission swap on my 540 auto. Great timing on my part, I will have to endure the worst the UK has to throw at me in terms of weather.

Trans is toast, see previous thread. Here I have sourced a used one, risky I know but these cars are worth a lot less over here. I have a rebuilt valve body to go into it.

What I am looking for is do's and don'ts, tips and tricks and any other priceless nuggets of information from people who have carried this out in the past.

Having been under the car for about a day already to remove the exhaust and heatshields I can see it looks like a pretty tight squeeze getting the box out past the headers. Do i need to remove the roll bar? Should I remove the torque converter with the box or slide it out over it and leave it attached to the flywheel? Any tips on removing the flex disc bolts (very tight, and big)? will the engine flop forward when the trans comes off or is it quite well balanced on it's own mounts?

That sort of thing .....:D

It would be silly not to put the questions out there with all the combined knowledge on this board.... so.... there we go.


Many thanks in advance.

Stephen.

I did the hard way. But it is a 6 speed conversion.

http://i21.photobucket.com/albums/b2...0/DSC_3131.jpg

the engine will rest fine, the converter bolts are no big deal as when the engine trys to turn over the socket that you are using on the bolt hits the side of the hole and stops it's rotation, that tranny is massive and ungodly heavy so be prepared, make damn sure you have the converter all of the way into the tranny when you are installing it, if it's not all of the way in and you force it in with the bellhousing bolts you will destroy the pump and booger up the snout of the converter at best, at worst frag the whole tranny

Right.... Happy New year everyone... Here I am with an update on my progress and another question.

The Trans is out now:) . All went suprisingly smoothly, no major PITA bolts to remove from the bellhousing, no clearance issues when dropping the trans, prop came off easily etc. Really pleased with progress so far, and thanks to Winfred for the reassurance.

I don't know if I've done the right thing here, but I left the Torque Convertor bolted to the flywheel when dropping the box. From your post Winfred, I see that your prefered method would be to unbolt the torque convertor and drop it with the Trans? So my first question is, should I mount it into the bellhousing for reinstallation to ensure a good 'mating' of the splined nose?

Secondly, when manhandling my used tranny (upside down and still containing some fluid) I notice fluid weeping from the input shaft. Anyone know if this is to be expected? Is this a sign of a shot input bearing seal? Should such items be replaced as a matter of course during a job such as this? What is invloved?

Is there any other maintenance that I should carry out while I have access to these areas of the vehicle that rarely see daylight?

In the mean time, I'll be swapping in my rebuilt valve body and trying to recruit a helper for the install, next weekend if all goes well.

Look forward to reading any advice you all may have.

Many thanks

Steve

Thanks

Quote:

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Originally Posted by blue540

I don't know if I've done the right thing here, but I left the Torque Convertor bolted to the flywheel when dropping the box. From your post Winfred, I see that your prefered method would be to unbolt the torque convertor and drop it with the Trans? So my first question is, should I mount it into the bellhousing for reinstallation to ensure a good 'mating' of the splined nose?
Thanks

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Maybe the 540 is different from mine but IMHO the torque converter MUST be in the gearbox before you install. Apart from damaging the seal, you need to spin the TC and push it inwards to get it to seat in the gearbox fully. If you are dropping the valve body anyway, check that the resistances of the speed sensors and valves are to spec. If any are duff now is the time to replace them. I found the box easier to install than a manual but it is VERY heavy-maybe 80kg+ on yours. I put mine with a forklift - the sideshift was great for the 'up a bit, right a bit' phase. You wont have one in your drive so you might want to rig up some kind of cradle for your trolley jack to make sure the box doesnt fall off.

Right, I'll get it off the flywheel tomorrow.

Any ideas on the input shaft oil seal anyone? I dont think this should be allowing fluid past.

Any suggestions as to what could be going on here. Bodged removal by dismantler?????

Quote:

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Originally Posted by blue540

Right, I'll get it off the flywheel tomorrow.

Any ideas on the input shaft oil seal anyone? I dont think this should be allowing fluid past.

Any suggestions as to what could be going on here. Bodged removal by dismantler?????

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This may sound a little stupid. If you dont have the TC in and you tip up the back end of the gearbox, ATF will pour out of the front seal. The TC fits in there and stops the oil coming out:) Well it should do - so its prudent to check that seal is OK before you put the TC back in. By the way, are you using the TC from the 'new' box or your old one?

Very interesting, keep us posted with progress, I'm watching this closely. Are you taking pics? Is this a pro only job or can a DIY mechanic do it as well?

Can you replace the torque converter without removing the whole box?

What was wrong with your old box? Sorry I can't give any advice but you wouldn't want any from me anyway when it comes to gearboxes.

Quote:

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Originally Posted by whiskychaser

This may sound a little stupid. If you dont have the TC in and you tip up the back end of the gearbox, ATF will pour out of the front seal. The TC fits in there and stops the oil coming out:) Well it should do - so its prudent to check that seal is OK before you put the TC back in. By the way, are you using the TC from the 'new' box or your old one?

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Thanks for that, could be just what is happening. Guess I just saw the fluid and paniced a little, assuming it was coming form the shaft seal. Seems silly now I think about it properly.

Quote:

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Originally Posted by whiskychaser

By the way, are you using the TC from the 'new' box or your old one?

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I dont have another torque convertor so the old one is going back in. While on the subject, I've read that it's very important to mark where the torque convertor sits on the shaft. Why is this critical?

http://bimmerboard.com/forums/posts/64818

I would have thought that the position of the torque convertor on the shaft would not be 'adjustable' so to speak?

Quote:

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Originally Posted by leicesterboy15

Very interesting, keep us posted with progress, I'm watching this closely. Are you taking pics? Is this a pro only job or can a DIY mechanic do it as well?

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I will grab some pictures tomorrow (today). Particulary of the nasty exhaust down pipe bolt configuration, total nightmare to remove. Especially when nuts have all but rusted away.

As for being a DIY job, kind of depends on how much of gluten for punishment you are. I am totally prepared for this not to work at all. No guarantee with a second hand box from ebay. I have swapped a 5hp18 in an E38 before, so I kind of knew what I was expecting. Hardest bit is getting the car high enough in the air. Creative use of concrete blocks required.

Quote:

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Originally Posted by leicesterboy15

Can you replace the torque converter without removing the whole box?

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In short, No.

Quote:

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Originally Posted by leicesterboy15

What was wrong with your old box? Sorry I can't give any advice but you wouldn't want any from me anyway when it comes to gearboxes.

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Old box suffered snapped off reverse clutch pack retaining clips (I think), lost reverse all together and found small bits of metal on top of the valve body upon removal. See link in first post for pics. I was pleased not to find similar pieces of broken metal in the 'New' box.

I dont have another torque convertor so the old one is going back in. While on the subject, I've read that it's very important to mark where the torque convertor sits on the shaft. Why is this critical?

I think what he meant was he marked the TC position in the bellhousing so he would know how when it was fully 'home'. (There is a gear inside the TC that engages in the gearbox) Put the TC in the box then spin it slowly while pushing it in. It will probably go back a couple of inches. Worth noting his warnings about ATF lurking in the TC and behind the filter:)

My box has a delay when engaging reverse for the 1st time, any subsequent time in quick succession is fine. And I think my torque converter is going, car feels like a turbo, no power until 3k rpm then it just takes off. Also if I plant my foot on take off I hear all sorts of nasty metallic noises from underneath as it takes off so I have stopped doing this, kind of nursing it for now until I get time and money for a sort out, I am prepared to replace the trans, ideally with a 6 speed manual but other things need doing first and my house is taking up all my money :(

Thanks for the info, if the box has to come out to replace the TC I may as well get it reconditioned at the same time. Car has 138k and I suspect the fluid has never been changed. I just can't find a good mechanic to sort me out!

Quote:

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Originally Posted by leicesterboy15

My box has a delay when engaging reverse for the 1st time, any subsequent time in quick succession is fine. And I think my torque converter is going, car feels like a turbo, no power until 3k rpm then it just takes off.

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Valve body rebuild or even just new fluid and filter may sort out your delay.

Quote:

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Originally Posted by leicesterboy15

Also if I plant my foot on take off I hear all sorts of nasty metallic noises from underneath as it takes off so I have stopped doing this, kind of nursing it for now until I get time and money for a sort out, I am prepared to replace the trans, ideally with a 6 speed manual but other things need doing first and my house is taking up all my money :(

Thanks for the info, if the box has to come out to replace the TC I may as well get it reconditioned at the same time. Car has 138k and I suspect the fluid has never been changed. I just can't find a good mechanic to sort me out!

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I had some nastly metalic rubbing too, turns out my gearbox mounts were shagged along with one engine mount too. The engine and box were twisiting and causing the prop to rub on the heatshields.

You can see in this pic where it has worn the paint of the prop (rusty bit) right next to the coupling. You can also see the shiny bit of heatshield directly above it where it was rubbing.

http://i158.photobucket.com/albums/t...Gearbox003.jpg

Great pic! Was it easier to leave the flexidisc on the prop? Seem to remember there wasnt room to get at those front bolts on mine so I left it on the box. Isnt there something about having to be careful which bolts you torque when you put it back together or you chew it up? Mine 'looked' OK but got a new one anyway

Quote:

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Originally Posted by whiskychaser

Great pic! Was it easier to leave the flexidisc on the prop? Seem to remember there wasnt room to get at those front bolts on mine so I left it on the box. Isnt there something about having to be careful which bolts you torque when you put it back together or you chew it up? Mine 'looked' OK but got a new one anyway

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Hello, big delay in reply but better late than never I suppose.

I found that I could not undo the bolts that would leave the disc on the box, I did go for those ones first but couldn't budge them. Managed to get to the others Ok. Bit of a nasty task of having to lift one wheel and drop into neutral to spin the prop so as to be able to get to all 3 fixings though, especially as the car was so high up on blocks already.

Here's some more pics......

http://i158.photobucket.com/albums/t...Gearbox014.jpg
Jacked up nice and high, this takes ages and is quite a hairy procedure. E34's are heavy.

http://i158.photobucket.com/albums/t...Gearbox009.jpg
One of the biggest problems I had was with the exhaust header to Cat joints. This pic shows how each side has 2 differing ways of attaching each of the two pipes. One set has studs inserted through form the rear of the flange, these are a splined interference fit and I could see no way of removing them. Why would you want to remove them you may ask? Because 3 of the 4 sheared or had to be cut because the nut on the other end had rusted to nothing. The other pipes have square nuts tack welded to the back of the flange for you to insert the bolt into. 3 out of 4 of the these square nuts also broke free during removal.

I then had to very carefully drill out the 3 broken studs. As this metal has been subjected to lots of heat it is very hard. After grinding them off back to the flange, I used 3 different size cobalt drills in each stud, 3mm to begin with, and only going in 4 to 5mm at a time before opening up the pilot hole with a larger drill. I did not want to snap off 40mm of cobalt drill in my studs!!!

To refit I just used nuts and bolts, it's a bit tricky getting access to the back of the flanges obviously, which why BMW arranged it like they did.


http://i158.photobucket.com/albums/t...Gearbox041.jpg
These are my CATS. I have holed one of them on the pipe section. See below.
http://i158.photobucket.com/albums/t...Gearbox043.jpg
All the scrappers I have looked at have different shaped units though so I have not been able to replace. This hole now has a piece of Baked bean can hose clamped to it with lots of Gun Gum.

Reached 5 Pic Limit, part two.


http://i158.photobucket.com/albums/t...Gearbox033.jpg
I figured it was worth replacing the input shaft seal while I was able to. Be careful removing the old one, I did not have any kind of puller device so had to carefully deform the seal inward with a screwdriver to enable me to remove it. There is a washer behind this seal, be sure to put it back in place before you drive in your new seal.... Especially if your method of removal destroys the seal. Seal is only £7 os so, but it really screwed up my Sunday when realised I had left the washer out having just driven my new seal in.

http://i158.photobucket.com/albums/t...Gearbox020.jpg
Amazed me when I saw that all the power and torque form the V8 is transferred to the torque convertor by this thin plate of stainless bolted to the flywheel.

Any ways, all fitted back together OK. It was hard handing over £200 to BMW stealer for fluid but it had to be done. I filled using a long piece of hose and big funnel. Relied on Gravity to push the fluid ino the box. When it started to drop out the bottom I would start the engine and run throught the gears, then get back out a put in more fluid until it began to flow out constantly.

Once I dropped it off the blocks I was unable to properly test the level so I took it to a BMW specialist to Top up.

I've put about 1000 miles on it now with no problems (touch wood). Rebuilt valve body seems to be working well, nice smooth shifts. It can be a bit notchy when cold but I can live with that.

All in it cost me about £450. Fluid was more than the box itself (ebay special).

I wonder what will break next......

Thanks for all your help.