aaaaaahhhhhhhhh. Looks scary, but it is a good thing you know what you are doing. Good Post and congrats!

 

Wow I agree. I can do engines and anything else but tranys just scare me.

 

Excellent information and good diagnosis/work on your part. I'm curious if you have previous experience going into a tranny or was this your first time?

I rebuilt my ZF transmission's valve body in a 7 series and it took me about 3 days. It was my first attempt at opening a transmission and I got quite a bit of help over the phone (while under the car).

 

AustralianM5, if you are ever up on the Sunshine Coast...........:hihi:

 

Great post and pics. Thanks for the info.

 

Great post. For future reference, what are the P/N's for the sleeve kit and locking pin? Is the access cover on the left or right side?

 

AustralianM5, if you are ever up on the Sunshine Coast...........:hihi:

Or Sydney!:cheers: :thumbsup:

Well done mate!

 

The actual repair kit is 23 31 7 506 947

Pretty amazing work I must say... well done, since you are in Melbourne, perhaps I will take the initiative and take you out for a cold one as a thanks from the entire board

 

Your tranny looks like it is in very good shape just at a glance. Gear edges look great with minmal wear. I would not have expected such a clean box since you said the car has had a "hard" life thus far..

 

All, thanks for positive feedback and offers of a drink, this messageboard has saved me some serious expense in the last 12 months and I was happy to make a contribution to this boards knowledge base.

Bimmernut1: You will laugh at this, as a hobbyist I have rebuilt many manual transmissions from rear wheel drive Peugeots built during the period 1949 to 1980 and also the 3 speed auto which is near identical to a GM trimatic. This is the totality of my experience with transmissions.
<O</O
Fifty Five: Access to the arresters is on the rear right, up top of the trans, you can see this in the photos. Supposedly the arresters can be changed with the trans in the car but that looked too hard to me and in my case unsticking the stuck ball would not have been possible. The locking pin can be changed easily with the trans in place.
<O</O
Rmd190: You are correct the gear and bearing faces looked quite good despite the oils condition and the miles on the car. The lifetime oil may be better that some suggest. The magnet in the bottom of the trans was covered in a film of stuff but the only chunks of metal were from the locking pin. I have been told the original owner often left the dealership with the wheels smoking and the car had the engine replaced early in its life.

 

Yup... your car had a hard early life but its come through with flying colours. Alpine White is a fantastic colour imho

 

Wow, what a fabulous report. I know I won't be finding myself doing this sort of thing any time soon, but I still read it all and looked at all the pics. Excellent.

 

That, my friend, was a great find! I must congratulate you on an excellent diagnosis! Great pictures as well! Thanks for sharing!:cheers:

 

Absolutely fantastic! Thanks. this is good to save, and move to archives.
I ran into a guy at a local event a few months ago, that had this same problem. He ended up forking out a couple of grand for a new tranny. The aftermarket warranty refused to pay b/c they said the detent balls were not internally lubricated! He was fighting it, but, it sounded as if he was giving in. I wish we could have helped him out. I told him to keep his old tranny as I thought it could be fixed. Maybe I will run into him again, or I hope he took my advice to check out this forum! Toasting an oil can (big Fosters) to ya!

Think it could be done without removing the tranny? Assuming bits and pieces were not floating around.

ernest

 

Aus

I echo the response from everyone else - the gearbox is diabolical to shift, and it just gets tighter and tighter. FINALLY! Someone decodes the problem!

Please take a look at the diagram in the link below - I'm guessing that you replaced items 17 (the kit) and 8-9-10. Is this correct? What about pins 1 and 5? They look like the same part for other shift rods.

http://www.realoem.com/bmw/showparts.do?model=DE93&mospid=47592&btnr=23_0887&hg=23&fg=15&hl=35

And, just so I know for sure - you replaced the arrestor balls because the shifting was hard, and the locking pin because it was broken. One change is an "upgrade" and the other is a "repair" to return it to original function. Do I have it correct?

Thanks!

JJ

 

Well done Mate, I have printed this out and given it to my mechanics, any parts you Aussie guys require please contact me as I have wrecked many e39's and import aftermarket and OEM for all Euro makes.

 

Well done Mate, I have printed this out and given it to my mechanics, any parts you Aussie guys require please contact me as I have wrecked many e39's and import aftermarket and OEM for all Euro makes.

Interesting .. I'll keep it in mind.. I normally use BM's R Us here in Melborne but they often dont have the parts im after or at a reasonable price

 

yeah they are pretty good, I have German Wrecking in Brisbane as well as European Wrecking, BM's R us are a customer of ours. Nice car mate !!!

 

Absolutely fantastic! Thanks. this is good to save, and move to archives.

Ditto.

I'll figure out how to link to this in a sticky perhaps!

Thanks for the effort.

A

 

Could this mod possibly help get rid of notchiness?

 

Jaj

Thanks and
<O
Yes all the parts under 17 come in the kit, 3 sleeves, 3 new springs and little cover plate and 2 bolts so I replaced all of these. In respect of the locking pin I only changed part number 8, this was the broken part in my photos.
<O
In relation to your last point I believe that the locking pin has been in poor shape since I bought the car 12 months ago, I think it contributed to the problem by stopping the mainshaft returning to the true neutral point before another gate was selected.
<O
However the part that jammed the box in reverse was the ball for the reverse detent, it was stuck, I manually aligned the other three slave selector shafts and immediately the reverse ball popped up and the transmission was then unjammed. The replacement sleeves would not get jammed out of line the way that a ball can, the damage or distortion to the lower part of the bore in the aluminium housing is irrelevant to the sleeves because they are supported over the length of the parallel sides. I think both issues had a part in the jamming and stiffness process.
<O
I can confirm that the shift is really very pleasant to use now and passengers have commented that my driving seems smoother now? I guess since I am not fighting with a recalcitrant gear shift I am more relaxed.
<O
Craigrhyne
This fixed the notchiness in the mechanism but does not make any difference the baulkiness of the actual engaging of gears so if your synchros are worn this will of course not alter that situation. My car seem worst at being taken out of a gear, other than reverse 6<SUP>th</SUP> also seemed to be affected first.
<O
Germanwrecker I never knew you existed!

 

<?XML:NAMESPACE PREFIX = O /><O< p><O< p><O< p><O< p><O< p>This fixed the notchiness in the mechanism but does not make any difference the baulkiness of the actual engaging of gears so if your synchros are worn this will of course not alter that situation. My car seem worst at being taken out of a gear, other than reverse 6<SUP>th</SUP> also seemed to be affected first.

<O< p>

I mis-shifted my 2002 M5 two days ago and now 4th gear has alomst no notchiness to it, while all the others feel unchanged. What is the best way for me to determine if my synchros are at fault or if the problem is actually in the detents or locking pins. I believe it is the synchros because if I attempt to shift without using the clutch, 4th gear grinds now, unlike previously.

Also, what model Getrag gearbox is in the M5?
</O<></O<></O<></O<></O<></O<>

 

Folks need to note this car was a 1999 model. The later "upgrade" version detents were a running production change in 2000, so this only applies to early M5. If you enter various mfg dates in realoemdotcom, this will become apparent.

This retrofit is described in BMW TIS and ETK.

Stiff shifting is quite widespread in later 2001 through 2003 M5 and 540i trannys with higher miles and/or neglected lubricant. It is often caused by worn synchro slider assemblies, bad lock pins, bent forks and/or worn detent notches in the rails. Broken lock pins can jamb in the shift rail tube & this prevents the transmission from being disassembled without case damage.

 

Lscman, you didn't mention the arresters and locking pins a few weeks ago when we were discussing this, your business I guess. Based on your words in earlier posts I carefully inspected the aspects of which you have written in relation to shift stiffness. Agreed then that locking pins are part of the problem and its handy that these are a 15 minute job to remove check and replace if necessary.

Now the comment about worn detent notches puzzles me, perhaps I have misunderstood here. The selector shafts in my transmission were either case hardened or just a hard material and these showed barely any marking at all even where the broken locking pin had been rubbing against the main selector shaft only superficial scratching resulted.

Now the selector forks in my box also showed no signs major wear or distortion, and I guess that this is confirmed by the fact that gear changes in my M5 are quite good now. Perhaps my transmission was not abused enough by its original owner or maybe the shift forks in later M5s are an inferior design. I have heard about the older M3 forks that were notoriously weak and would spread and so not adequately locate the synchro/gear change assemblies one symptom of which was jumping out of gear.

I was actually impressed at the construction of most of the change mechanism, the selector shafts, run in either linear ball bushing bearings or some in teflon coated bushes both of which offer a consistent low friction operation.

For later M5s then I think it may still be worth a quick look at the arrester sleeves to see if they are lubricated, if the bleed hole in each sleeve is clear and to see if the sleeves show any sign of scuffing. Yesterday a local independent BMW service centre called and suggested that they had to replace the sleeves in a Z4 because of stiff shifting. Different transmission obviously but similar detent system where sleeves were original fitment and the scoring on these sleeves caused a stiff shift problem.

 

The detent replacement procedure is clearly documented in BMW factory service literature & it is accurate. Sorry but after discussing this topic, I assumed you read TIS. Internet sites have links for it too & it's no secret. That said, very few folks have success with that procedure & I can surely not simplify it. Recommending this repair is a double edged sword because other's have learned the hard way, including myself, plus a few folks I tried to advise and a couple BMW trained mechanics that I bought spares from. This may be why the TIS procedure is seldom used under warranty. I had a fellow on roadfly email me for advice and then threaten me after his stiff shifting 540i tranny (pulled for a clutch replacement) suddenly became 100% non-functional. I was 0 for 3 trying to advise how to replace detents and lock pins, so I gave up 6 mo ago. If the detent balls are removed while in the wrong gear or the selector shaft is disturbed with the detents removed, the tranny shift selector arm will lose synchronism and lock up solid. You apparently discovered this before tearing the tranny apart or when trying to reassemble. Trying to resynchronize the fork shafts through the detent holes is difficult and generally impossible, unless maybe they only moved slightly. The chance of scoring the machined holes during prying exercise is high.

Many stiff-shifting newer M5 and 540i cars have the later type detents and the problem is not reliably fixed by detent replacement. A good BMW tech told me this is why BMW replaces boxes...the detent upgrade often results in little or no improvement and they were eating the jobs. My 1998 540i had stiff shifting yet behavior did not improve much with the later detent upgrade. Rebuild & mods were needed to maximize shift quality and performance of my tranny. Results will vary wrt changing a few parts because tranny condition, service history, vintage, synchros, driver behavior & mileage seems to mean a lot.

The lifecycle of the fork shafts varies significantly & I am not clear why. This may be a lubricity/stiction problem or varying hardness of the shafts used in different vintage trannys. The aluminum forks definitely bend because the wear pattern is not even on some forks with perfectly straight shafts. The '99 and early '00 M5 trannys were a bit different than later years. They seem to have superior internal parts in certain areas & stronger intermediate cases. The large number of factory reman trannys found in M5's (replaced under warranty) makes it tough to confirm differences (accurately extrapolate). Although later year trannys have improved sleeve detents, the case and other internal hardware was watered down a bit..sharing more internals with 540i and E46 M3. My experience is admittedly sketchy. Lifecycle may also be a function of driver shifting behaviors. Some shafts wear severely where the detents ride and where they pass through a ball sleeve bearings. The bearings act as if they are bound up or lacking lubrication. Most rear cases become damaged beyond repair when the locking pin breaks. The pin splits and mushrooms, tearing up and stretching the bronze sleeve that it rides in & making it almost impossible to extract. The loose roller end generally gets jambed into the aluminum case by the selector shaft movement and this means the case busts when you disassemble the tranny. Sometimes it gets crammed all the way through the rod hole and finds it's way into the oil. The chance of a gear inhaling it is high, long before it finds the magnet.

Very few lock pins break "gracefully", allowing you to fish out the broken parts & reuse the case. Lock pins can fail in 15K miles or 150K miles. According to my experience and some BMW dealer tech feedback, abusive shifting causes them to break, not some magic number of miles. I doubt if they have much impact on shift effort until they fail. You clearly did not continue to force the shifter into gear after breakage, so damage was not so catastrophic.

 

AustralianM5,

Welcome to the board and Thanks for a great thread!

David

 

AustralianM5,

I decided to 1/4 mile drag my car on the strip and after 5 runs I noticed that I have a hard time getting into first gear.....but it is not consistent sometimes its fine and sometimes its harder than usual but it engages....I have a Z3M short shifter which is extremely short and hard to shift from the start...but 1st gear and reverse gears (only)...randomly sometime engage easily and sometimes with more than usual effort......is your guess tranny damage...if so what components? ...would the repair kit possibly help? ...my build date is 9/1999

Thanks!

 

You have early style detents. That said, the upgrade kit described in TIS and ETK will probably not help much if the stiffness symptom is "intermittent when hot". This symptom you describe is typically associated with wear of the internal rail bearings and synchro sliders which allows gates, sliders and forks to become misaligned slightly and catch instead of moving across each other smoothly. With excess wear, depending upon the way you enter the next gate, the shifter might hit a "false stop/wall" or slide in freely. The slightest change in lateral positioning or force on the shifter will produce a different feel or result, if certain components are worn.

The later style detent kits can sometimes improve cold stiffness a bit on higher mile early trannys. This is not a cure-all because the shift internals have fundamental weaknesses that lead to stiffness/notchiness with growing miles & wear.

This is why many newer 2001+ Getrag trannys with the updated detents (kit) have stiffness issues too. The problem was NEVER really fixed by Getrag. This detent/lock kit was a positive step, but not a proper design fix.

Another possibility.......I don't know what tranny fluid you're running. Ther's a slim possibility that your tranny fluid is too thin to provide smooth shift rail operation after it heats up with repeated drag racing runs. You might try a thicker viscosity such as OEM fill.