Transmission fault 08 535
02-08-2016, 06:56 AM
#31
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My Ride: 545i sport
Model Year: 2004
4F81 is a 'ratio monitoring' fault in the A drum of the transmission. Bascially, the TCU detected slip in the A drum. Some of us get that fault, some of us get 4F85 which is the same fault for the E drum. I've had both stored in my TCU at some point in time. It usually appears during downshifts for me. A fluid and filter change made the car shift slightly better, but I still got it once after servicing my gearbox.
The rectangle seal you mention is the bridge seal between the Mechatronic (valve body) and the transmission housing. It is prone to failure, as are the solenoids that control the gear shifts. My guess is that at 100K, it's likely a little bit of 'all of the above'.
My 530i is at 104K and has given me 4F85 a couple of times this year. I plan on replacing the solenoids, bridge seal, and sealing sleeve. Replacing the bridge seal does require that the Mechatronic be completely removed from the car. Removing the Mechatronic requires a fluid drain and removal of the sealing sleeve. Replacing the solenoids requires all of the same steps, which is why in my opinion is makes sense to replace the solenoids, bridge seal, sealing sleeve, and any other common failure point while you have everything apart and the Mechatronic out of the transmission.
Imagine how frustrating it would be to just replace the bridge seal, get the car back together, only to find out you needed shift solenoids too. If you plan on keeping the car long term, I'd just do all of the above OR buy a completely rebuilt Mechatronic. Obviously there's a significant cost difference, so you'd have to weigh your options.
I wouldn't reuse the fluid. I also wouldn't reuse the pan, which has the filter integrated into it. If you've never serviced your transmission and you plan on keeping the car long term, I'd bite the bullet and spend the 1K in parts and do it right. I ordered all of my stuff from thectsc.com.
good luck with the car, is it just me or is there an absolute rash of transmission problems being posted as of late? ZF.....ugh.
The rectangle seal you mention is the bridge seal between the Mechatronic (valve body) and the transmission housing. It is prone to failure, as are the solenoids that control the gear shifts. My guess is that at 100K, it's likely a little bit of 'all of the above'.
My 530i is at 104K and has given me 4F85 a couple of times this year. I plan on replacing the solenoids, bridge seal, and sealing sleeve. Replacing the bridge seal does require that the Mechatronic be completely removed from the car. Removing the Mechatronic requires a fluid drain and removal of the sealing sleeve. Replacing the solenoids requires all of the same steps, which is why in my opinion is makes sense to replace the solenoids, bridge seal, sealing sleeve, and any other common failure point while you have everything apart and the Mechatronic out of the transmission.
Imagine how frustrating it would be to just replace the bridge seal, get the car back together, only to find out you needed shift solenoids too. If you plan on keeping the car long term, I'd just do all of the above OR buy a completely rebuilt Mechatronic. Obviously there's a significant cost difference, so you'd have to weigh your options.
I wouldn't reuse the fluid. I also wouldn't reuse the pan, which has the filter integrated into it. If you've never serviced your transmission and you plan on keeping the car long term, I'd bite the bullet and spend the 1K in parts and do it right. I ordered all of my stuff from thectsc.com.
good luck with the car, is it just me or is there an absolute rash of transmission problems being posted as of late? ZF.....ugh.
Actually, the bridge seal seals the interface between the transmission oil pump and the valve body. So, all oil leaving the pump under pressure is directed into the valve body first. So, you can understand how important this seal is to the operation of the transmission. Also, in addition to the mechatronic sleeve, the four rubber tubes sealing valve body to transmission case should also be replaced as all fluid leaving the valve body and headed to the clutch packs is sealed by these four tubes. To remove the tubes, I simply screw a lag bolt into the rubber tubes and pull them straight out.
03-08-2017, 10:53 AM
#32
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My Ride: 2008 535i
Pavrom,
I got two of the codes on my car (4F84 and 4F97) and dealer service is saying that I need to replace the entire trsnamission.
What was the fix on your car. Your help is greatly appreciated.
Bashar
I got two of the codes on my car (4F84 and 4F97) and dealer service is saying that I need to replace the entire trsnamission.
What was the fix on your car. Your help is greatly appreciated.
Bashar
03-08-2017, 08:21 PM
#33
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My Ride: E60 2006 sedan auto
I have fixed 5 transmissions that BMW had told the owners to replace it with a new one
Just follow the advice on this post
replace your seals but I also replaced the electric selectors on the valve body on my car
Its been two years and its still running perfect
03-10-2017, 07:26 PM
#34
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My local stealer once tried to sell a co-worker a $7000 transmission replacement and all that was wrong was low fluid due to a leak at the cooler on the rad. They said the oil leak was engine oil as it was brown. When she bought 4L of OE fluid and found it was brown...
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