sxctme 0 Report post Posted January 6, 2010 I have done a search and cant really find any help with this. I have a e34 525i m50 with 4 speed auto trans (no dipstick if it helps) with the s e and * switch. When i drive it cold (in the mornings or after sitting at work all day) it slams into 2nd gear quite violently, however if i put it into * mode (im guesing means snow) it drives perfectly smooth also after about 20mins of driveing (in e or s) it gets better untill eventually its perfect again. I did a trans flush at my work was told by parts supplyer there isnt a filter in the trans i find it hard to believe but took their word for it and refilled it with dex 3 atf which was reccomended by oil supplyer. Changing the atf has not helped at all Any ideas on what to do next? I dont really want to just chuck a second hand trans in if i can fix the old one myself Thanks Quote Share this post Link to post Share on other sites
Mark 178 Report post Posted January 6, 2010 (edited) Jap import car? Sounds like you have the dreaded "Jatco Jerk". The problem generally occurs between 1st and 2nd gear. The reason it doesn't happen when you have Winter mode selected on the transmission is because this instructs the transmission to start off in 2nd gear. I had this exact problem on my E36 and I documented my attempt to fix the problem here: Jatco Jerk - Official thread To be honest, the easiest (EDIT: and cheapest) way to solve the problem is either a manual conversion, or replace the auto with the ZF trans. Edited January 6, 2010 by _Mark_ Quote Share this post Link to post Share on other sites
sxctme 0 Report post Posted January 6, 2010 Jap import car? Sounds like you have the dreaded "Jatco Jerk". The problem generally occurs between 1st and 2nd gear. The reason it doesn't happen when you have Winter mode selected on the transmission is because this instructs the transmission to start off in 2nd gear. I had this exact problem on my E36 and I documented my attempt to fix the problem here: Jatco Jerk - Official thread To be honest, the easiest (EDIT: and cheapest) way to solve the problem is either a manual conversion, or replace the auto with the ZF trans. Ahuh thankyou that has helped me alot . now to decide to do it myself or pay someone. i am a mechanic but not too flash on the auto gear boxes they give me a headahce just looking at them Quote Share this post Link to post Share on other sites
sxctme 0 Report post Posted January 6, 2010 Jap import car? Sounds like you have the dreaded "Jatco Jerk". The problem generally occurs between 1st and 2nd gear. The reason it doesn't happen when you have Winter mode selected on the transmission is because this instructs the transmission to start off in 2nd gear. I had this exact problem on my E36 and I documented my attempt to fix the problem here: Jatco Jerk - Official thread To be honest, the easiest (EDIT: and cheapest) way to solve the problem is either a manual conversion, or replace the auto with the ZF trans. What is involved in changing to a zf trans? ecu driveshaft etc? dont really want to go manual atm Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted January 6, 2010 What is involved in changing to a zf trans? ecu driveshaft etc? dont really want to go manual atmdont bother swapping to zf , as they are rare , and yes wou will have to swap the driveshaft and the trans computer and trans wiring loom etc . just convert it to a manual.or put another jatco box in , . try reseting the trans computer Quote Share this post Link to post Share on other sites
Wom 0 Report post Posted January 6, 2010 mine required a full overhaul ... $3,000 worth (luckily my car is under warranty) ... probably cheaper to replace with a good working 2nd hand box if you can do the work yourself but yea try resetting the computer first like Brent said, have read that it solves the issue for some people Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted January 6, 2010 I can look at it for you later today if you'd like. Call me first 2722546 Quote Share this post Link to post Share on other sites
kiwi328i 118 Report post Posted January 14, 2010 I have this same problem (like numerous others, with an E36) and I am going to replace it with a ZF Auto (which I have) shortly, but even thats not all painless, I am almost inclined to get a 'good' secondhand jatco and put it in and save for a manual conversion, but unless the car you have is 'unpartable' its probably easier AND cheaper to replace the car. Apparently these Jatco's to fix are not financially viable, to expensive in the first place and are still inherently unreliable. I have done a search and cant really find any help with this. I have a e34 525i m50 with 4 speed auto trans (no dipstick if it helps) with the s e and * switch. When i drive it cold (in the mornings or after sitting at work all day) it slams into 2nd gear quite violently, however if i put it into * mode (im guesing means snow) it drives perfectly smooth also after about 20mins of driveing (in e or s) it gets better untill eventually its perfect again. I did a trans flush at my work was told by parts supplyer there isnt a filter in the trans i find it hard to believe but took their word for it and refilled it with dex 3 atf which was reccomended by oil supplyer. Changing the atf has not helped at all Any ideas on what to do next? I dont really want to just chuck a second hand trans in if i can fix the old one myself Thanks Quote Share this post Link to post Share on other sites
bekker 7 Report post Posted January 14, 2010 I had the exact same problem in a Honda Legend (notoriously weak transmissions). The 1st - 2nd clutch pack was shot. There was no easy fix, although this product helped reduce the severity - http://www.lubegard.com/~/C-230/Dr.+Tranny...nt+Shudder+Fixx I think BNT sell it. Like I said, it won't fix a worn clutch pack, but it might reduce the pain until you find another box. Good luck. Quote Share this post Link to post Share on other sites
BM WORLD 1283 Report post Posted January 14, 2010 I have this same problem (like numerous others, with an E36) and I am going to replace it with a ZF Auto (which I have) shortly, but even thats not all painless, I am almost inclined to get a 'good' secondhand jatco and put it in and save for a manual conversion, but unless the car you have is 'unpartable' its probably easier AND cheaper to replace the car. Apparently these Jatco's to fix are not financially viable, to expensive in the first place and are still inherently unreliable. can you sawp a zf auto in . i thought the loom and trans ecu are different] i have a good low km jatco that came from amy 96 328i with 100k on it left over from when i converted it to a manual . Quote Share this post Link to post Share on other sites
*Glenn* 854 Report post Posted January 14, 2010 (edited) can you sawp a zf auto in . i thought the loom and trans ecu are different] DME will be different as well... which could also lead to the MAF being different too And EWS could be an issue if the car has it and the donor doesnt A 95 E36 runs seperate bus lines for ABS & ZKE. But DME & EGS use the same line and need to talk to each other to work Edited January 14, 2010 by *Glenn* Quote Share this post Link to post Share on other sites
kiwi328i 118 Report post Posted January 22, 2010 can you sawp a zf auto in . i thought the loom and trans ecu are different] i have a good low km jatco that came from amy 96 328i with 100k on it left over from when i converted it to a manual . My one started playin up around the 138k mark and my mates is already playin up at 89k, so its either Magyver the ZF in, or rebuild the flippin thing. Yeah trans ecu is different, but I will be gettin that soonish, so hopefully fingers crossed its just the wiring, but saying JUST the wiring is a mistake. As far as I can tell, its going to require some creativity lets say if I do go down this route. Unless you have 2 hoists and got a nz new car and a jatco one side by side up in the air, its hard to tell what you can and cannot play with. I may swap out Mums ecu from her 1998 e36 320i, and give that a whirl first, and see what happens, bit I dont like me chances. I like to think when BMW designed the e36 to receive different auto boxes in other parts of the world, it had a simple modular concept in mind. It doesnt help that as far as I can tell, no-one has attempted this yet, or maybe they are not telling.lol. Quote Share this post Link to post Share on other sites