Torque Converter failure....symptoms???

[Mewsy]

M20, Auto box with no electronic switch, mechanic has diagnosed over phone that the torque converter is u/s, and will be inbetween $1000 - 1800 AUD to repair/replace. Haven't had time to get in to see him.
Symptoms that i have is when i reach 80-90kph, the gear box changes into 'lock out' like a fifth gear. When it does this i get an initial noticable vibration that continues slightly, and the car feels like it is surging slightly. It started doing this gradually, and I have noticed a little tranny fluid on the front outer gearbox casing. No other problems with the gear box, still feels as strong as ever and shifts well. Only other recent problem that may be associated is my rear muffler has developed a large hole at the inlet pipes. Is it possibly just a seal that has failed on the torque converter, and also does that seem an excessive price on repairs.
Thanks
Garry - Perth

[ryan roopnarine]

which transmission is your vehicle equipped with. us model 525i (m50 engine) were equipped with a GM transmission that would surge around 55-60 mph (88-102 kph) when a set of gaskets would fail, and also leak tranny fluid from where the torque converter housing connects to the rest of the transmission body.

[Mewsy]

which transmission is your vehicle equipped with. us model 525i (m50 engine) were equipped with a GM transmission that would surge around 55-60 mph (88-102 kph) when a set of gaskets would fail, and also leak tranny fluid from where the torque converter housing connects to the rest of the transmission body.

it is a 4hp22. It is a euro spec car delivered new in Australia. It is a 4 speed auto that does not have the a/s/m electronic switch next to it. Only reason I question whether the whole torque converter needs replacing, is that I found torque converter seals for sale on a parts web site, and there is some leaky fluid on the casing, but not enough leaking to drop on my dirveway.

[Bellicose Right Winger]

There's a service bulletin in the TIS on the early 4hp22's regarding vibration as the TC goes into lockup. I know it covers 535's, not sure if it covers 525's also. I'm out of town and can't give you the bulletin no, maybe another board member can post it, or better yet post the bulletin. Seems on some vehicles the TC went into and out of lockup very rapidly causing the vibration. I think it was a solenoid problem. If this isn't the problem, I'd get out the ETM and figure out how to disconnect the wire that engages lockup, before I replaced the TC. Fuel mile will take a hit though. Does the vibration go away if you shift into 3rd just before trans goes into lockup?

Paul Shovestul

M20, Auto box with no electronic switch, mechanic has diagnosed over phone that the torque converter is u/s, and will be inbetween $1000 - 1800 AUD to repair/replace. Haven't had time to get in to see him.
Symptoms that i have is when i reach 80-90kph, the gear box changes into 'lock out' like a fifth gear. When it does this i get an initial noticable vibration that continues slightly, and the car feels like it is surging slightly. It started doing this gradually, and I have noticed a little tranny fluid on the front outer gearbox casing. No other problems with the gear box, still feels as strong as ever and shifts well. Only other recent problem that may be associated is my rear muffler has developed a large hole at the inlet pipes. Is it possibly just a seal that has failed on the torque converter, and also does that seem an excessive price on repairs.
Thanks
Garry - Perth

[Mewsy]

There's a service bulletin in the TIS on the early 4hp22's regarding vibration as the TC goes into lockup. I know it covers 535's, not sure if it covers 525's also. I'm out of town and can't give you the bulletin no, maybe another board member can post it, or better yet post the bulletin. Seems on some vehicles the TC went into and out of lockup very rapidly causing the vibration. I think it was a solenoid problem. If this isn't the problem, I'd get out the ETM and figure out how to disconnect the wire that engages lockup, before I replaced the TC. Fuel mile will take a hit though. Does the vibration go away if you shift into 3rd just before trans goes into lockup?

Paul Shovestul

The gearbox kicks down instantly, holds all gears as it should, and basically has no other problems!