Hello all thanks for reading,
Builder replaced the failed B-Drum, valve body, hard parts and the torque converter on a ZF5HP24. So now the car engages into drive and reverse hard and vehicle lurches/lunges when doing so. When coasting to a stop the car bucks as it is downshifts thru the gears. Bucks harder when applying the brakes on your way to the stop light. Up shifting is relatively smooth but not near as smooth as it was before the drum failure. Sometimes, normal driving 30-40 mph, car seems to "hickup" like it cant decide on what gear to use. There is no slipping or a delay in gear engagements. Traveling at highway speeds, say 60-65mph, and i want to pounce the pedal to the floor it will kick down and engage with a very hard bang that shakes the whole car. Also does this when headed up a steep fast canyon. (this is similar to when the B-Drum originally failed and I was at a dead stop and in drive I increased the rpm when it "found/banged" into fourth gear lunging the car forward, skid the tires and the gearbox fault light comes on putting it in limp home mode, felt like someone hit me from behind, really rattles your chain.) I have done this carpet kick down before the rebuild many times and I remember it would do two quick kick down shifts but now it seems like its hoping over a gear and slamming into the next lower gear.
It does any or all of the above scenarios pretty much 90% of the time but sometimes it shifts into drive or reverse normally. After the kickdown bang it wont do that anymore until i shut off the engine. The downshift lurching is there all the time. Dosent matter if the outside temperature is 100 degrees or 25 degrees or when engine is warm or cold.
The transmission fluid runs hot at 225 degrees.
Rebuilder swapped the valve body three times thinking it was a bore issue but with no change.
No codes or warning lights or messages present.
Idle is normal at 650rpm.
Trans fluid cooler in radiator is unobstructed as well as the lines per builder inspection.
Fluid is up to level assuming it was filled with the correct procedure per builder inspection.
Battery is at 12v but it is 4 years old.
No corrosion on pins at Transmission Control Module or Engine Control Module.
Throttle position sensor working tested with live feed code reader per builder.
Is this a torque converter problem that is causing the shifting problems (shifts bad when hot and or cold) and then it is just heating up the fluid to 225 degrees or is it the wrong fluid in there that just wont shift properly at all (shifts bad when hot and or cold) and is just heating up to 225 degrees cause it cant handle the mechanical dynamics of a more sophisticated transmission or is the trans fluid temp sensor faulty (hot or cold) telling the TCM to protect itself because it thinks the fluid is 225 degrees, But wouldent a bad trans temp sensor throw a code? Keep in mind that the car was already hot when the 225 degree reading was "discovered". builder did not put the reader on when the car was cold to watch the temp climb.
Torque converter problem. Could be it has just failed somewhere inside like a sealing ring or something, separated somewhere, or its just a cheap one that cant handle the demands of the ZF. The big question, whats causing this fluid to heat up?
Fluid problem? Before the original rebuild work was started I specified it needs to be ESSO/Mobile LT 71141 or Lifeguard Fluid 5 honey yellow in color. After the original rebuild complete with a "new" rebuilt or remanufactured Sonnax valve body I got the car back assuming it was the ESSO in the trans..... Took it for a drive and all the shifting problems were there right from the start. Took for another drive with the rebuilder sitting shotgun and the live feed code reader hooked up and he got the 225 degree fluid reading and nothing else, no codes, no flags, no lights. We did test the throttle position sensor percentage at 100%. Builder put in another valve body stating it was a problem with the bore(s) causing to much high line pressure. When I got back from a 2 hour lunch and window shopping around the city I noticed the "faulty/new/old" valve body on the table with red fluid all over it. I inquired he said "not to worry the red "spec fluid LT71141" that I used is not the problem it was the valve body." I thought LT71141 was yellow... Car got finished I took for a drive and exhibited the exact same shifting problems described above. Took it back again for the third valve body and a concern of the red "spec fluid" being used. Same story, red spec fluid is fine. So now three valve body's later it is still exhibiting the exact same shifting problems as it did with the second and first valve bodies. And it still has this red fluid it it, I know this because the pan gasket is now leaking slightly.
Thanks again.
Jon
Builder replaced the failed B-Drum, valve body, hard parts and the torque converter on a ZF5HP24. So now the car engages into drive and reverse hard and vehicle lurches/lunges when doing so. When coasting to a stop the car bucks as it is downshifts thru the gears. Bucks harder when applying the brakes on your way to the stop light. Up shifting is relatively smooth but not near as smooth as it was before the drum failure. Sometimes, normal driving 30-40 mph, car seems to "hickup" like it cant decide on what gear to use. There is no slipping or a delay in gear engagements. Traveling at highway speeds, say 60-65mph, and i want to pounce the pedal to the floor it will kick down and engage with a very hard bang that shakes the whole car. Also does this when headed up a steep fast canyon. (this is similar to when the B-Drum originally failed and I was at a dead stop and in drive I increased the rpm when it "found/banged" into fourth gear lunging the car forward, skid the tires and the gearbox fault light comes on putting it in limp home mode, felt like someone hit me from behind, really rattles your chain.) I have done this carpet kick down before the rebuild many times and I remember it would do two quick kick down shifts but now it seems like its hoping over a gear and slamming into the next lower gear.
It does any or all of the above scenarios pretty much 90% of the time but sometimes it shifts into drive or reverse normally. After the kickdown bang it wont do that anymore until i shut off the engine. The downshift lurching is there all the time. Dosent matter if the outside temperature is 100 degrees or 25 degrees or when engine is warm or cold.
The transmission fluid runs hot at 225 degrees.
Rebuilder swapped the valve body three times thinking it was a bore issue but with no change.
No codes or warning lights or messages present.
Idle is normal at 650rpm.
Trans fluid cooler in radiator is unobstructed as well as the lines per builder inspection.
Fluid is up to level assuming it was filled with the correct procedure per builder inspection.
Battery is at 12v but it is 4 years old.
No corrosion on pins at Transmission Control Module or Engine Control Module.
Throttle position sensor working tested with live feed code reader per builder.
Is this a torque converter problem that is causing the shifting problems (shifts bad when hot and or cold) and then it is just heating up the fluid to 225 degrees or is it the wrong fluid in there that just wont shift properly at all (shifts bad when hot and or cold) and is just heating up to 225 degrees cause it cant handle the mechanical dynamics of a more sophisticated transmission or is the trans fluid temp sensor faulty (hot or cold) telling the TCM to protect itself because it thinks the fluid is 225 degrees, But wouldent a bad trans temp sensor throw a code? Keep in mind that the car was already hot when the 225 degree reading was "discovered". builder did not put the reader on when the car was cold to watch the temp climb.
Torque converter problem. Could be it has just failed somewhere inside like a sealing ring or something, separated somewhere, or its just a cheap one that cant handle the demands of the ZF. The big question, whats causing this fluid to heat up?
Fluid problem? Before the original rebuild work was started I specified it needs to be ESSO/Mobile LT 71141 or Lifeguard Fluid 5 honey yellow in color. After the original rebuild complete with a "new" rebuilt or remanufactured Sonnax valve body I got the car back assuming it was the ESSO in the trans..... Took it for a drive and all the shifting problems were there right from the start. Took for another drive with the rebuilder sitting shotgun and the live feed code reader hooked up and he got the 225 degree fluid reading and nothing else, no codes, no flags, no lights. We did test the throttle position sensor percentage at 100%. Builder put in another valve body stating it was a problem with the bore(s) causing to much high line pressure. When I got back from a 2 hour lunch and window shopping around the city I noticed the "faulty/new/old" valve body on the table with red fluid all over it. I inquired he said "not to worry the red "spec fluid LT71141" that I used is not the problem it was the valve body." I thought LT71141 was yellow... Car got finished I took for a drive and exhibited the exact same shifting problems described above. Took it back again for the third valve body and a concern of the red "spec fluid" being used. Same story, red spec fluid is fine. So now three valve body's later it is still exhibiting the exact same shifting problems as it did with the second and first valve bodies. And it still has this red fluid it it, I know this because the pan gasket is now leaking slightly.
Thanks again.
Jon
