transmission help!!!

[555]

i have a 90 e34 with a m20, and when i am going 45mph or so the trans can not decide if it want to be in 3rd or 4th? it just keep shifting 3-4-3-4.... espcially when going up hill could someone please help me and let me know what is wrong with it? before some shop or dealer rip me off!!! thanks.

[Randell]

try searching the forum for 'pendulum shifting', sounds like that could be your problem

[Kalevera]

i have a 90 e34 with a m20, and when i am going 45mph or so the trans can not decide if it want to be in 3rd or 4th? it just keep shifting 3-4-3-4.... espcially when going up hill could someone please help me and let me know what is wrong with it? before some shop or dealer rip me off!!! thanks.

On those things, all you can do is assure that the kickdown cable is accurately adjusted and that the fluid level is correct (and that the fluid itself isn't indicative of a dead trans). Beyond that, it's a valve body issue.


best, whit

[555]

thanks for the info. i have check those items and they seem to be find, so i told it to bmw dealer and they said i need to replace the trans could that be true? they want $3500 for the job. that's a bit much for me. so i'm thinking to track down a use or rebuild trans. does anyone know which model trans would fit my car? that's beside a 90' 525i with an m20 eng!

[tim s]

my 540i/a did that a couple of times. i replaced the switch & it has not done it since. there is a way to test the switch with a multi-meter, but i had my mech. do it.
tim s.

[Kalevera]

The BMW ZF Remanufactured Trans (Valueline) for your car costs the dealer a little less than $1300 and they'll retail it for $1995 or more. Labor rate on the trans job is something like 6 hours according to the pricing software, and dealers really stick it to the customer for it at around $150/hour. Price gouging and inflated labor rates are how the dealer makes money and one of a few reasons why you don't want to take the car to be serviced at one.

The critical reason is their uncanny ability to mess up and overlook everything -- they executed three errors (mis-installation and damaging mistakes) when they replaced my trans under BMW warranty. Trust me when I say that dealership service departments generally suck. Hence it's smart to visit a competent indy. Where are you located in the world? A good indy will sell you the same trans as the dealer, including the two year unlimited mileage warranty (serviceable at any BMW dealership, not that you'd want it to be), and offer a better rate on labor. If you find a shop from http://www.iaibmwsp.org, I can assure that the job will likely be done with the utmost care.

Alternatively, 5 speed parts for your car are relatively inexpensive. We've got a few M20 5 speed transmissions at the shop and plenty of other misc parts floating around. They're also readily available from most wreckers and on eBay.

The car has a ZF 4hp-22, non hydraulic (EH). I personally wouldn't stick a used unit in anybody's car, let alone my own. These trannies have a propensity to blow up from a few minor faults, and bargaining with a used unit (and the previous owner's habits/lack of care in changing the fluid and filter), or even a "warrantied" rebuild by a local shop, have the potential to be expensive mistakes.



best, whit

[Kalevera]

my 540i/a did that a couple of times. i replaced the switch & it has not done it since. there is a way to test the switch with a multi-meter, but i had my mech. do it.
tim s.

Tim, unlike the 5hp-30 in your car, the M20 525s have a non electrically controlled 4hp-22. The only interaction between the engine and transmission, beyond power transmission and the motronic flywheel position sensors mounted in the bellhousing, is a kickdown cable.

A faulty TPS is a good thought, though. A dirty throttle body could also confuse it.

best, whit

[555]

wow!!!!! whit, u sure know a lot about these cars. so a used trans is a bad idea! then would you said changing to a 5 speed is better then replacing the auto unit?

[Kalevera]

It has to do with preference -- some people prefer the automatic; some prefer a manual transmission. If you were to collect the parts and do the work yourself, you could accomplish the manual transmission conversion for less than $1500 with all new parts. In fact, I think The Euro Depot had a $995 sticker on the kit with new parts for M20 E30 cars...and the E34 isn't that different.

The 4hp-22 is an interesting transmission. We talk about it a lot around here and you'll probably dig up more than you want to read with a quick search of the forums. Winfred has a writeup on fixing two of the common mishaps with them. I'm a pundit of the 15,000 mile fluid and filter change. Once the fluid gets old and the filter gets partially clogged, it limits their lifespan considerably. Then there's the whole revving it in park and neutral issue, which you'll want to avoid at all costs (and a used trans will likely have leaky seals and worn frictions, anyway...not to mention the possibility for bad fluid and other types of neglect).


best, whit

[555]

thanks whit! i will look into these options. u have been a great help!