91 500SL with 722.353 transmission slipping
07-26-2015, 12:15 PM
#1
Newbie
Thread Starter
91 500SL with 722.353 transmission slipping
Hello all,
I have a problem with my gearbox that annoys me to bits. Any help would be highly appreciated.
I bought my car in August 2014 from a guy who was not technical at all. The gearbox was a bit sluggish but did not misbehave. I had the box flushed and the filter replaced. After some time I topped up the oil with a non approved ATF. Kroon 2042 ATF. Some weeks later the gears started slipping. shifting from 2-3 and from 3-4 under half load the engine revs up 300-400 rpm and after a second or two the next gear kicks in ever so gently. The gearbox shifts normally under full load. The reverse kicks in normally but feels like the handbrake is on.
What i have done so far:
- flushed the gearbox
- replaced the modulator and adjusted the modulator pressure, it already had the new style modulator.
- replaced oil and filters again
- checked the ATF oil level
- cleaned the valvebody and installed the K1 spring set, gear changes seem less erratic now. One spring seemed to be missing.
- checked bowden cable
- checked oil level and modulator pressure again.
I am wondering what the problem is and I am guessing that one of the previous owners has thrashed the box and the clutch plates. The options i can see now are:
- Put in lucas transmission fix to see if things improve
- open op the gearbox and check the clutch plates and brake bands and replace if needed.
Has anybody dealt with this problem before? The thing that keeps bugging me is that the box seemed to work OK in the beginning. They may have used transmission fix or something similar before?
Regards Frank
I have a problem with my gearbox that annoys me to bits. Any help would be highly appreciated.
I bought my car in August 2014 from a guy who was not technical at all. The gearbox was a bit sluggish but did not misbehave. I had the box flushed and the filter replaced. After some time I topped up the oil with a non approved ATF. Kroon 2042 ATF. Some weeks later the gears started slipping. shifting from 2-3 and from 3-4 under half load the engine revs up 300-400 rpm and after a second or two the next gear kicks in ever so gently. The gearbox shifts normally under full load. The reverse kicks in normally but feels like the handbrake is on.
What i have done so far:
- flushed the gearbox
- replaced the modulator and adjusted the modulator pressure, it already had the new style modulator.
- replaced oil and filters again
- checked the ATF oil level
- cleaned the valvebody and installed the K1 spring set, gear changes seem less erratic now. One spring seemed to be missing.
- checked bowden cable
- checked oil level and modulator pressure again.
I am wondering what the problem is and I am guessing that one of the previous owners has thrashed the box and the clutch plates. The options i can see now are:
- Put in lucas transmission fix to see if things improve
- open op the gearbox and check the clutch plates and brake bands and replace if needed.
Has anybody dealt with this problem before? The thing that keeps bugging me is that the box seemed to work OK in the beginning. They may have used transmission fix or something similar before?
Regards Frank
Last edited by wasterfd; 07-26-2015 at 12:18 PM.
07-27-2015, 08:43 AM
#2
did you drain the torque converter? it holds a lot of fluid and may have the unapproved fluid in it. also did you check where the wiring harness goes into to the tranny to see if the seal is good or weeping fluid. if it's leaking fluid check you fuse box on the i believe passenger side to see if there is any sign of fluid in there.
07-27-2015, 09:16 AM
#3
Newbie
Thread Starter
Hi Biker 349,
Thank you for your response. When I exchanged the oil last time I also drained the torque converter yes. My transmission is a mechanical one, does that also have a wiring harness? I think not but I will check.
Regards Frank
Thank you for your response. When I exchanged the oil last time I also drained the torque converter yes. My transmission is a mechanical one, does that also have a wiring harness? I think not but I will check.
Regards Frank
07-28-2015, 09:07 AM
#4
are you saying you have a stick shift? any progress? i would assume that there is a wiring harness in your tranny. if it's a stick shift then i'm not sure.
