[Bfrancom2]

Hi all!

I am looking for input about the reliability of the 8AT (ZF8HP50) found in B58 equipped cars.

I'm currently making about 550ftlbs at the crank. I'm not really worried about that. While it's over the 369 rating, I have faith as they're wildly underrated from the factory.

My question is, I am looking to upgrade my HPFP and in turn, I'd be doing about 650 ftlbs at the crank. Is this feasible on the 8AT?

**BEFORE ANYBODY COMMENTS** I don't want to hear "It's rated at 369....you're exceeding the specifications." No shit. I am looking for B58 owners on AUTO transmissions that have been making over 500wtq (600+ at the crank) and their experiences, mileages, etc.

Thank you!

[B58togo]

I'm currently at 55K. Tuned on JB4 since 1200 miles. DP added ~26,000. Went BM3 Stage 2 93 ~35,000, xHP Stage 3 on the ZF8 ~39,000, BM3 Stage 2 E30 + around 40,000. Upgraded to the Dorch Stage 1 ~50,000 and then went with a custom Paul Johnson tune shortly after. No issues at all. Guess I'm probably around 550 ft lbs @ the crank and maybe 480/500 wheel. I do have the OEM filter and fluid kit and plan to change it soon. There are others running upgraded turbo and making much more than me with no issues. Time will tell.

[Bfrancom2]

Originally Posted by B58togo

I'm currently at 55K. Tuned on JB4 since 1200 miles. DP added ~26,000. Went BM3 Stage 2 93 ~35,000, xHP Stage 3 on the ZF8 ~39,000, BM3 Stage 2 E30 + around 40,000. Upgraded to the Dorch Stage 1 ~50,000 and then went with a custom Paul Johnson tune shortly after. No issues at all. Guess I'm probably around 550 ft lbs @ the crank and maybe 480/500 wheel. I do have the OEM filter and fluid kit and plan to change it soon. There are others running upgraded turbo and making much more than me with no issues. Time will tell.

Ok thanks. I appreciate your input. I would be doing about 550tq to the wheels, really just scared for the longevity. I know it would be fine for quite some time but I'm wondering if it would fail very prematurely.

[Supr3me]

Just dyno'd 570/592 today, Dynojet.
XDrive 8AT, running xHP Stage 3 transmission flash. I'm at 56K miles and no issues.
But I'm quite proactive with maintenance. Depending on your mileage, I recommend doing transmission, diff, and transfer case services if you plan to increase your power level significantly- even tho BMW says some of those fluids are "lifetime".

[eksigned]

I'm on the Pure 800 setup, and while I haven't dyno'ed...I suspect just shy of 550 whp and just shy of 600 ft lbs. I'm at 41k and I've been on this setup for a little over 10k miles, with the MF trans flash having been on the car since a little over 15k. I AM tuned specifically though to have my torque come on stronger past 5.5k, with stock like feel and easy shifts down below at low rev levels. I also have the filter and fluid sitting in my garage to be swapped out shortly here. No problems, but I really try to be conservative with the car (daily driving at low revs) unless I'm doing freeway pulls.

Rumor has it though that 6th gear is the weak link in the HP50. I suspect though it's likely because of its perfect rpm when trying to do moderate pulls to pass cars etc. at freeway speeds - probably sees most of the abuse in terms of frequency.

[Bfrancom2]

Originally Posted by eksigned

I'm on the Pure 800 setup, and while I haven't dyno'ed...I suspect just shy of 550 whp and just shy of 600 ft lbs. I'm at 41k and I've been on this setup for a little over 10k miles, with the MF trans flash having been on the car since a little over 15k. I AM tuned specifically though to have my torque come on stronger past 5.5k, with stock like feel and easy shifts down below at low rev levels. I also have the filter and fluid sitting in my garage to be swapped out shortly here. No problems, but I really try to be conservative with the car (daily driving at low revs) unless I'm doing freeway pulls.

Rumor has it though that 6th gear is the weak link in the HP50. I suspect though it's likely because of its perfect rpm when trying to do moderate pulls to pass cars etc. at freeway speeds - probably sees most of the abuse in terms of frequency.

Gotcha. Yeah, makes sense. By fluid and filter you mean for the transmission? I'm just hitting 20k miles on my car so I'd prob be fine for some time right?

[m140guru]

Mine slips in 4/5th gears on high torque map with pure 800. Also 6th gear the trans slips bad that it has the ecu reduce boost by half. Car has around 22k miles (2018 model).

[JD11937]

I'm at 45,000 miles, 5,000 miles at around 530whp/tq and no slipping yet. I daily drive my car, I don't use launch control and don't abuse it but I drive it hard.

As many have mentioned I think fluid changes are important, doing mine any day now.

I'm sure it's not cheap to to repair but at least the zf trans is in so many cars.

[jackstrath]

Originally Posted by m140guru

Mine slips in 4/5th gears on high torque map with pure 800. Also 6th gear the trans slips bad that it has the ecu reduce boost by half. Car has around 22k miles (2018 model).

Have you got Xhp installed?

[m140guru]

Originally Posted by jackstrath

Have you got Xhp installed?

Yes ofcourse

[F30MGM]

Originally Posted by Bfrancom2

Hi all!

I am looking for input about the reliability of the 8AT (ZF8HP50) found in B58 equipped cars.

I'm currently making about 550ftlbs at the crank. I'm not really worried about that. While it's over the 369 rating, I have faith as they're wildly underrated from the factory.

My question is, I am looking to upgrade my HPFP and in turn, I'd be doing about 650 ftlbs at the crank. Is this feasible on the 8AT?

**BEFORE ANYBODY COMMENTS** I don't want to hear "It's rated at 369....you're exceeding the specifications." No shit. I am looking for B58 owners on AUTO transmissions that have been making over 500wtq (600+ at the crank) and their experiences, mileages, etc.

Thank you!

Swapped to zf8hp70 no issues here

[T_H_O_M_A_S]

do you have a topic about the swap ??

[Mr. 340]

Originally Posted by F30MGM

Swapped to zf8hp70 no issues here

Would love to hear more about this. Mind explaining how and when did you do this swap? Was it a direct bolt on?

[F30MGM]

Originally Posted by Alan340

Would love to hear more about this. Mind explaining how and when did you do this swap? Was it a direct bolt on?

Check my posts I posted a diy

[T_H_O_M_A_S]

https://f30.bimmerpost.com/forums/sh...ighlight=8hp70

??

[F30MGM]

Originally Posted by T_H_O_M_A_S

https://f30.bimmerpost.com/forums/sh...ighlight=8hp70

??

12.10.19 Final Update - Warranty Denied. DIY upgrading transmission to a USED ZF8HP70 https://f30.bimmerpost.com/forums/sh....php?t=1663852