KyleB

There is no sensor for fluid level as far as I know.

pcy

+1.

BMW put whole lot of sensors but no sensor for trans fluid level.

tonyb635

I don't think so either, but if the tranny is low on fluid I am curious what code would be visible.

pcy

You will _eventually_ see a big exclamation mark and a symbol of gear

tonyb635

The code that I have is 4F81 Looks like there are a couple of youtube videos out there showing how to repair it. Pan removed, then valve body and there is a black plastic rectangular seal of some kind that seems to crack and not allow fluid where its needed. Car goes in limp mode. The repair talks about reusing the fluid, I am not so sure I am interested in that... 100K I think she is ready for a new filter cover and fluid. As much as I want to attempt this repair, I honestly think I'll call and check around on costs.

KyleB

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.

KyleB

BTW, here is a really cool link to Exedy's website. Find a comfortable spot for about 45 minutes and watch the "6R80 rebuild" video. 6R80 is the Ford equivalent to ZFs 6HP26, which is very similar to the 6HP19 transmission. Watching this video will give you a very good understanding of how your transmission works.

EXEDY Learning Center - Home OE

Ben535xi

That is very interesting! Thanks for the link!

tonyb635

I called a tranny shop today and the cost is around 500 or 700 if I go with new fluid. They said with this electronic shift tranny that the sealing pressure block is most likely bad. They wear out over time and don't allow the pressure to build as needed. New pan and seals need to be replaced. The shop said they can filter and reuse the fluid or replace it. I don't think I will be reusing the fluid. My friend knows a guy who works for ZF and I called him today. He's going to stop by in a few to take a deeper look into the software to see exactly what the problem is. Ok I'll have another quote in a few. I'm just not up to doing this myself.

tonyb635

Good news, he ran the the checks and all looked very good. Will repair next weekend with all new parts and fresh oil for around 300. I'll drink some beer and watch and learn a little, then give him some beer when he finished!!!