Rebuilt Transmission Question.

[diyanich]

Hi guys,
I got a question about a tranny.
So,my tranny was slipping/shuttering @ 50 km/h every time after 20 min of summer driving or so,let's say when it worms up.
I brought it to get the tranny checked and guys in mr.Transmission said that it was slipping between 2 & 3 gear,so they needed to investigate more,so they removed the pan and filter and found out some friction material on the sponge like material on the inner side of the pan.
So,here the rebuild saga starts,instead of 5 business day anticipated I had to wait for precisely 2 weeks.
Well I test drove the X ,paid a pile of money and drove it home...
Here's where the fun begins...
I felt the same problem I had before the rebuild,but....@ 40 km/h and waaaaay smother,it only happens when I accelerate soft....
I am quiet shocked....
I don't think that it's a braking in issue,that is gonna disappear.
Torque converter - rebuilt
Friction material - new
Valve body - checked and 1 solenoid replaced.
150 km on the tranny right now.
I've reset the control unit....

Any suggestions?

Thankx

[Weasel]

If your X5 is 2004 and up it has the x-drive transfer case. In the case is a clutch pack just like in the transmission, and can cause exactly what you are describing. As a quick diagnosis method to see if it is the case as I suspect would be to simply unplug the actuator motor on the case. If you look under the X5 at the left rear side of the transfer case you will see a wiper motor sized motor, unplug it and go for a test drive. (you may get a DSC light on, but this is the easiest diagnosis) If the ride smooths out and feels normal with it unplugged, you may need a new unit. I think the new clutch friction plates may be available, but the motor has a coding plug that is determined by the clutch characteristics, and adaptations further adjust as you drive over the miles. You would need to register whatever is done in the VTG (transfer case control module) via the GT1 tester to clear adaptations for it.

[diyanich]

Hi Weasel!

Thank you for your reply.
Mine is 4.4 2000,so no X-Drive here.
I was told that there's a 500 kms breaking in for the friction material,I have feeling that it's not gonna disappear...
I feel that transmission overall acts fine,but I still have the rear endings when it warms up.
How about a transfer case for my model?
Also,why is it smoother now after a rebuild,so I suspect the issue should be within the tranny case.
Any idea is appreciated.

Originally Posted by Weasel

If your X5 is 2004 and up it has the x-drive transfer case. In the case is a clutch pack just like in the transmission, and can cause exactly what you are describing. As a quick diagnosis method to see if it is the case as I suspect would be to simply unplug the actuator motor on the case. If you look under the X5 at the left rear side of the transfer case you will see a wiper motor sized motor, unplug it and go for a test drive. (you may get a DSC light on, but this is the easiest diagnosis) If the ride smooths out and feels normal with it unplugged, you may need a new unit. I think the new clutch friction plates may be available, but the motor has a coding plug that is determined by the clutch characteristics, and adaptations further adjust as you drive over the miles. You would need to register whatever is done in the VTG (transfer case control module) via the GT1 tester to clear adaptations for it.

[Weasel]

Ok, pre x-drive has just a simple chain drive over some planetary gears.

In that case I'd just drive it easily, like grandmother would drive, until the friction plates wear in properly. Easy slow starts and longer slower stops will not only help in the proper breaking in process, but will also help store a smoother shift pattern in the adaptations. Just give it a few days and see what happens.

[diyanich]

Today I dropped by the transmission shop that had my tranny rebuilt and fortunately when the guy test drove it the shuttering happened.
So,we came back to the shop and he pulled some codes from the engine brain and tranny brain,I don't have them now,but it was something like CAN communication interruption,also there was a code for electronic brake distribution or so and a power shortage as well as an O2 sensor code.....
Also he said that my battery died on them once,well...
Can this BS be caused by something electrical? He says that yes,it can be,like if there's a shortage of power or insufficient power so 3rd gear solenoid is "shuttering" on off on off on off...so it releases the clutches and engages again....
What I know,that it's true that my battery is dying fast even if I charge it with the charger once a month...
Can all this be battery's fault.
Any opinion is appreciated.

Originally Posted by Weasel

Ok, pre x-drive has just a simple chain drive over some planetary gears.

In that case I'd just drive it easily, like grandmother would drive, until the friction plates wear in properly. Easy slow starts and longer slower stops will not only help in the proper breaking in process, but will also help store a smoother shift pattern in the adaptations. Just give it a few days and see what happens.

[Weasel]

If you are due for a battery and need it anyways, just get it to dispel it as a cause. I personally do not think the voltage is causing the solenoid to shudder, but they don't know the can bus complexity. I'd get the battery straight then have the faults cleared. Drive it a few days and see what codes come back if it still does it.

[diyanich]

I just made 750 kms and it does exactly the same as before rebuild with the same strengths but now it's @ 60 km/h instead of 50 before rebuilt and 40 right after.
I am so disappointed,
It's always a 3rd gear...
I've got a warranty with them,but I will get stuck without the X for a while...
Can it be the torque converter's fault? it was rebuilt,but why is it always a 3rd gear?

Originally Posted by Weasel

If you are due for a battery and need it anyways, just get it to dispel it as a cause. I personally do not think the voltage is causing the solenoid to shudder, but they don't know the can bus complexity. I'd get the battery straight then have the faults cleared. Drive it a few days and see what codes come back if it still does it.

[Dave Hill]

I have a 4.4 (year 2003) that has a "shudder" in 3rd gear too & It sounds similar to your problem. In my case, the shudder occurs, as the gearbox is about to shift into 4th, on a light throttle. If I am driving more "enthusiastically" the shudder doesn't happen.

I have found that if I drive it in sports mode the the shudder never happens. I have come to the conclusion that the torque converter lock up solenoid is "having trouble" when in standard drive mode

I think the shift sequence is a little more basic when in sports mode & the solenoid is not used to "smooth the shift in the same way as it does in standard auto.

I am not sure what to do about my problem. Maybe a genuine BMW unit is the way forward. I worry about paying big money for a repair or a refurbished unit. At least a genuine exchange unit will have all the important bits brand new & a good guarantee to go with it.

Good luck with your problem.

Regards

Dave

[diyanich]

Thank yo fr the reply.
That shuddering doesn't happen in the Sports mode,it's only happening when the engine just got to the operating temps and slight throttle is applied.
But for example if I drove it for a while on the Free Way when I go on the streets it shudders like a hell at random speeds in the 3rd gear.
My guess is that fluid gets really thin so it slips a lot.But always always the same gear.
The torque converter along Valve body were checked by the Mr.Transmission HUB in Quebec.Converter was rebuilt.
I am getting sick of it.
Can it be a software glitch?
I don't really know what else to do,I can't let my car sit for weeks while they randomly try to get to the cause.

Originally Posted by Dave Hill

I have a 4.4 (year 2003) that has a "shudder" in 3rd gear too & It sounds similar to your problem. In my case, the shudder occurs, as the gearbox is about to shift into 4th, on a light throttle. If I am driving more "enthusiastically" the shudder doesn't happen.

I have found that if I drive it in sports mode the the shudder never happens. I have come to the conclusion that the torque converter lock up solenoid is "having trouble" when in standard drive mode

I think the shift sequence is a little more basic when in sports mode & the solenoid is not used to "smooth the shift in the same way as it does in standard auto.

I am not sure what to do about my problem. Maybe a genuine BMW unit is the way forward. I worry about paying big money for a repair or a refurbished unit. At least a genuine exchange unit will have all the important bits brand new & a good guarantee to go with it.

Good luck with your problem.

Regards

Dave

[JohnD]

Have you had your rear differential fluid checked? I had a 328IS with the same problem you describe and after countless hours trying to diagnose a transmission issue a friend suggested replacing the differential fluid, and it cleared the problem