e53 hard downshift is killin me

[BMWLOVER]

Originally Posted by spamking98

Im on my third tranny... gosh... im startin to miss my honda

Just got a phone call and they said they are going to replace tranny at just 35,000km. This sucks. My explorer and impala both at 400,000km both have orignial tranny and never had problems.

[CharlieHustleX5]

Any Idea how much the charge is if you're out of warranty?

[FeltBikeRider]

Bringing up an old post to share my experience with this issue.

2005 BMW X5 4.4i

Had the bang a few times. A couple times starting from a stop sign or red light. A couple times from a rolling stop >5 mph ...

I also had a bit of a rocking chair feel when torque converter clutch was engaged at low speeds such as 30-45mph 1,250 rpm-1,000 rpm.

I put the car on the lift as it was new to me within the last 3 months and my extended warranty was days from expiring.

What I found was the mechatronic sleeve was leaking and there was some fluid around the pan area in the rear by the transfer case. It isn't what I would consider an extreme leak. More of a seeping slowish leak. Who knows how long it was leaking however (no puddles/spots on the driveway or my parking spot at work)...

Anyways, I decided dropping the pan and replacing the filter would be a good idea. I got the mechatronic sealing sleeve as well. I got my pan gasket/ filter, mechatronic sleeve, and fluid (ZF Lifeguard 6) from BMW Parts and BMW Accessories | Bavarian Autosport for a hefty fee. Upon dropping the pan and replacing the gasket I couldn't figure out how to remove the sealing sleeve.... I was told how to do it by a friend who was incorrect in his explaination.

The fluid that came out was terribly dark, there were even some chunks in it when I poured it through a paint strainer into a jug to measure the amount I took out. I tried to replace the mechatronic sleeve but felt like I might break it and decided to leave it. I inteded on doing a second flush in a few weeks and figured I would do it then.

I filled the system though the bottom of the pan (there are 2 styles of pans and filling systems) using my Snapon scan tool monitoring the temperature of the transmission fluid. Unfortunately after a long day of work I set the scan tool up to monitor engine temp by mistake (they are right next to each other and I'm an idiot) ...


So anyways, you fill the pan with fluid until a stream comes out with the engine off... then you start the vehicle, cycle through the gears and leave the vehicle running with the scan tool hooked up to monitor Transmission fluid temp in Celcius.

Raise the vehicle and begin filling with fluid again until a stead stream comes out the fill port. Now you wait until the transmission fluid reaches between 40-50c. As you wait more and more fluid will spill out as the fluid heats up and expands. When you hit about 45c you put the fill plug back in. It's a good idea to clean up with some parts cleaner so you will know if you have a leak after you're done.

So at this point I thought I was gravy... test drove the car around for 5-10 minutes...it drove great. A few days later we took the car to my inlaws for Christmas Eve... its about 100 miles round trip... No issues. Christmas morning on a cold start and little warmup time I headed out to my parents. I got a pretty significant bang on my first 4 or 5 1-2 shifts.... then as the vehicle warmed up it stopped. When I got to my parents I looked under the car and saw a good amount of fluid coming from the mechatronic sleeve I was unable to replace.

The following Monday I brought the car into my shop and drained it again and dropped the pan. I found an explanation of how to replace the mechatronic sleeve online searching in ZF6HP26 transmission manuals. YOU NEED TO PULL DOWN ON A WHITE CLIP that retains the mechatronic sleeve inside the transmission. It then easily pulls out.

I then re-did the entire fill procedure with new ZF fluid making sure I was monitoring transmission fluid temp this time. So far so good. The car has been driving great and I have not had any issues or leaks.



SUMMARY - I think low fluid level is plaguing most BMW drivers with this ZF6HP26 transmission. Because BMW claims the fluid is lifetime (Mind you the ZF manual says 65,000 miles or 100 kilometers) people aren't servicing them and the mechatronic sleeve leaking is SUPER common. Because there is no dipstick tube or dipstick to check your level people just assume everything is ok. The ZF transmission seems to be very particular about fluid level.. The filter pulls fluid from the front of the transmission pan. When you are on an incline (where I hear a lot of people complain about the banging being the worst) the fluid is pulled to the back of the pan by gravity and it is more likely to get a gulp of air when fluid levels are questionable.

It is also possible that the nasty fluid was wreaking havoc in the valve body and causing poor shifting. Either way a drain and fill or better yet a pan drop with new filter is a great idea. This fluid was NEVER meant to be lifetime. Shame on BMW for making such a claim.

I hope this helps anyone with this issue. Don't hesitate to ask questions... it's not a hard job it's just annoying and requires a good fluid transfer pump (Bav auto sells 2, mine needed minor modification) the right tools, and a little understanding of how to do the procedure (YES A SCAN TOOL REALLY IS NECESSARY to do it right) or you can use a laser thermometer on the bottom of the pan for a rough estimate.

[admranger]

Originally Posted by FeltBikeRider

Bringing up an old post to share my experience with this issue.

2005 BMW X5 4.4i

Had the bang a few times. A couple times starting from a stop sign or red light. A couple times from a rolling stop >5 mph ...

I also had a bit of a rocking chair feel when torque converter clutch was engaged at low speeds such as 30-45mph 1,250 rpm-1,000 rpm.

I put the car on the lift as it was new to me within the last 3 months and my extended warranty was days from expiring.

What I found was the mechatronic sleeve was leaking and there was some fluid around the pan area in the rear by the transfer case. It isn't what I would consider an extreme leak. More of a seeping slowish leak. Who knows how long it was leaking however (no puddles/spots on the driveway or my parking spot at work)...

Anyways, I decided dropping the pan and replacing the filter would be a good idea. I got the mechatronic sealing sleeve as well. I got my pan gasket/ filter, mechatronic sleeve, and fluid (ZF Lifeguard 6) from BMW Parts and BMW Accessories | Bavarian Autosport for a hefty fee. Upon dropping the pan and replacing the gasket I couldn't figure out how to remove the sealing sleeve.... I was told how to do it by a friend who was incorrect in his explaination.

The fluid that came out was terribly dark, there were even some chunks in it when I poured it through a paint strainer into a jug to measure the amount I took out. I tried to replace the mechatronic sleeve but felt like I might break it and decided to leave it. I inteded on doing a second flush in a few weeks and figured I would do it then.

I filled the system though the bottom of the pan (there are 2 styles of pans and filling systems) using my Snapon scan tool monitoring the temperature of the transmission fluid. Unfortunately after a long day of work I set the scan tool up to monitor engine temp by mistake (they are right next to each other and I'm an idiot) ...


So anyways, you fill the pan with fluid until a stream comes out with the engine off... then you start the vehicle, cycle through the gears and leave the vehicle running with the scan tool hooked up to monitor Transmission fluid temp in Celcius.

Raise the vehicle and begin filling with fluid again until a stead stream comes out the fill port. Now you wait until the transmission fluid reaches between 40-50c. As you wait more and more fluid will spill out as the fluid heats up and expands. When you hit about 45c you put the fill plug back in. It's a good idea to clean up with some parts cleaner so you will know if you have a leak after you're done.

So at this point I thought I was gravy... test drove the car around for 5-10 minutes...it drove great. A few days later we took the car to my inlaws for Christmas Eve... its about 100 miles round trip... No issues. Christmas morning on a cold start and little warmup time I headed out to my parents. I got a pretty significant bang on my first 4 or 5 1-2 shifts.... then as the vehicle warmed up it stopped. When I got to my parents I looked under the car and saw a good amount of fluid coming from the mechatronic sleeve I was unable to replace.

The following Monday I brought the car into my shop and drained it again and dropped the pan. I found an explanation of how to replace the mechatronic sleeve online searching in ZF6HP26 transmission manuals. YOU NEED TO PULL DOWN ON A WHITE CLIP that retains the mechatronic sleeve inside the transmission. It then easily pulls out.

I then re-did the entire fill procedure with new ZF fluid making sure I was monitoring transmission fluid temp this time. So far so good. The car has been driving great and I have not had any issues or leaks.



SUMMARY - I think low fluid level is plaguing most BMW drivers with this ZF6HP26 transmission. Because BMW claims the fluid is lifetime (Mind you the ZF manual says 65,000 miles or 100 kilometers) people aren't servicing them and the mechatronic sleeve leaking is SUPER common. Because there is no dipstick tube or dipstick to check your level people just assume everything is ok. The ZF transmission seems to be very particular about fluid level.. The filter pulls fluid from the front of the transmission pan. When you are on an incline (where I hear a lot of people complain about the banging being the worst) the fluid is pulled to the back of the pan by gravity and it is more likely to get a gulp of air when fluid levels are questionable.

It is also possible that the nasty fluid was wreaking havoc in the valve body and causing poor shifting. Either way a drain and fill or better yet a pan drop with new filter is a great idea. This fluid was NEVER meant to be lifetime. Shame on BMW for making such a claim.

I hope this helps anyone with this issue. Don't hesitate to ask questions... it's not a hard job it's just annoying and requires a good fluid transfer pump (Bav auto sells 2, mine needed minor modification) the right tools, and a little understanding of how to do the procedure (YES A SCAN TOOL REALLY IS NECESSARY to do it right) or you can use a laser thermometer on the bottom of the pan for a rough estimate.

Great post! Thanks for the tip on removing the tube. Mine isn't leaking (furiously knocking on wood), it's nice to know how to take it off if it ever does.

How much fluid did you determine needs to be put back in for a pan drop fluid change?

[bcredliner]

Suggest you take it to a well recommended transmission shop that is familiar with BMW transmissions for diagnosis.