1991 525i Trans Program fixed

[Alexander Rosa]

I have a 91 525i w/ automatic transmission and M50 engine. This model came with a GM 4L30e transmission made in France. My scenario went like the following:

In the morning, as long as my car remained cold, it ran perfect. Tranny shifted beautifully. As soon as temperature had risen to full warmth, Trans Program error would come up and tranny would default to 3rd gear (limp mode, failsafe mode). Although, I drove my car, starting out in manual 2nd gear and shifting to manual 3rd. Since my car worked when cold I knew my tranny was OK. I inspected everything, from bad switches to bad sensors in engine, bad alternator to bad battery. Finally I had the car scanned and it turned out to be exactly what I supected all along. It was a bad "Band Apply Solenoid", sometimes called a brake band apply solenoid valve. Anyway, BMW dealer wanted $155 for the part. I went to an aftermarket wholesaler called DACCO, they sold me the same part made by General Motors for $45. Keep in mind I asked for the part by tranny model, never mention what car it's for. GM 4L30e, also used in Isuzu Rodeo and Cadillac Catera. Anyway, to make the story short, it took me 15 minutes to take main tranny pan off, remove filter, solenoid is the only solenoid at rear of tranny above filter held by a small metal pin that slides out. Solenoid slides right out. Then remove two-wire connector that attaches to solenoid. Installation is same as reverse. Put everything back together and Voila!!! NO MORE TRANS PROGRAM ERROR!!! Now this tranny takes me up to 60mph at 6500 rpm in 1ST GEAR!!! Faith in BMW restored.

If you have this same issue, email me for further instructions, pics and all diagrams involved. By the way, I asked real experts all over the country, they all said the same thing..."That solenoid goes bad all the damn time on those 4L30e transmissions!"

Big Al Rosa
91 525 iA
87 325 es+i
Audi 5000 CStA

[Daless]

[tudm]

is that the same tranny that is in all 91 525\'s ?? i just replaced the engine in mine with a Vanos \'95 block ... my tranny is shifting from 1st to 2nd really quick ... then a slight \"shudder\" from 2nd to 3rd ... then it is fine ... it is bearly noticeable, but im pretty [Oops!] retentive about my car...lol when i had the trans out i did see a plate that said GM on it(but i didnt pay attention to the model number) i was too involved in spicing the wiring harness to make the new computer run the vanos.

i can DEFFINITELY tell the difference in the engine power and torque .. although it is the most aniemic of the 4 BMW\'s that ive owned ... i think that the solenoid u are talking about might fix this problem ... please e-mail me with more info

thanks, in advance, for your help
Mike Teague
'91 525i 188,000 Miles W/
'95 M50 VANOS Engine
THE ULTIMATE DRIVING MACHINE

[Alexander Rosa]

All 91 525's with M50 engine have GM 4L30e tranny, definitely if you see a GM stamp on it. These transmissions were used supposedly because of their overall hauling potential, given that the 525i is one heavy [Oops!] car. From studies, I think it has more cons than pros. For one, it doesn't seem to handle raw torque too well, although I push my tranny hard. Then again, the M50 engine is only a 2.5L inline 6cyl. The ZF trannies seem to have better integrity, but the GM tranny is really a horsepower transmission made more for top end speed rather than off-the-line speed.Meaning it is more of a light truck transmission or 4x4 tranny if anything, with a strong 1st gear that builds RPM's like a rock, yet isn't too fast, thanks to tall final gear. My car seems to have a different final gear and my 1st gear is wicked, although I don't think it's healthy at all for my tranny. I have been really scheptical toward the whole thing and truthfully was disheartened to find out I had a General Motors cheap [Oops!] tranny in my High Performace German Engineered power machine of a car. Since then, I've been scared to push my car too hard. On the bright side, I could probably replaced this transmission if it ever blows up on me for under $500...

[chinto velez]

Alexander, I have more or less the same problem, so I wpould really apreciate it if you could send me more info and diagrams. Also if you have any info or steps for cleaning/replacing thegear selector swithc and the speed sensor. I want to see all possibilities.
thanks beforehand Al,
Chinto

[Unregistered]

im having similar problems. Did the problem ever come back with yours.