[GF]

Does anyone know what the max torque load is for a manual gear box on a 2018 340i xDrive?

Thanks for your time.

[bimmer456]

Originally Posted by GF

Does anyone know what the max torque load is for a manual gear box on a 2018 340i xDrive?

Thanks for your time.

355 lb ft if going by mppsk for manual transmission. The unit in the M3/4 would be able to handle more. It can probably handle more with a jb4 without self destructing but that would be outside warranty.

[GF]

Originally Posted by bimmer456

355 lb ft if going by mppsk for manual transmission. The unit in the M3/4 would be able to handle more. It can probably handle more with a jb4 without self destructing but that would be outside warranty.

I have mppsk and I'm looking at Dinan elite v2 which will add about 50TQ. My concern is how much extra clutch wear this will cause . . .

[ZTZ1010]

Originally Posted by bimmer456

355 lb ft if going by mppsk for manual transmission. The unit in the M3/4 would be able to handle more. It can probably handle more with a jb4 without self destructing but that would be outside warranty.

this is incorrect. Just because MPPSK raises tq to 355 doesn't mean that is the hardware limit. There is always a buffer zone built in from the factory, and there are PLENTY of stock clutch cars making more than 355 without issue.

[bimmer456]

Originally Posted by ZTZ1010

this is incorrect. Just because MPPSK raises tq to 355 doesn't mean that is the hardware limit. There is always a buffer zone built in from the factory, and there are PLENTY of stock clutch cars making more than 355 without issue.

The mppsk raises torque to 369 for automatics it is only raised to 355 for manuals. That's the level they are comfortable with to not have any issues with the clutch.

[ZTZ1010]

Originally Posted by bimmer456

The mppsk raises torque to 369 for automatics it is only raised to 355 for manuals. That's the level they are comfortable with to not have any issues with the clutch.

Your logic is flawed.

Based on your theory, the S55 6MT would be hardware limited at ZCP power levels since that's where BMW pegged it. However, we know the trans is sufficient for much higher power levels than that. It's much more likely that BMW wanted to "push" 6MT buyers looking for bigger power from the factory into M2s or F8Xs. Keep in mind how conscious BMW is of "softening" models to keep them far enough away from M cars.

The factory HP ratings are not necessarily indicative of hardware limitations.

[G.Newt]

Not a whole lot of info on the internet about torque numbers for our ZF 6-speed manual.

http://www.realoem.com/bmw/enUS/show...diagId=23_1123

[bimmer456]

Originally Posted by ZTZ1010

Your logic is flawed.

Based on your theory, the S55 6MT would be hardware limited at ZCP power levels since that's where BMW pegged it. However, we know the trans is sufficient for much higher power levels than that. It's much more likely that BMW wanted to "push" 6MT buyers looking for bigger power from the factory into M2s or F8Xs. Keep in mind how conscious BMW is of "softening" models to keep them far enough away from M cars.

The factory HP ratings are not necessarily indicative of hardware limitations.

I already said it could handle more but that is what they will cover with warranty. You can tune it all you want with jb4 to over 400 horsepower. It might be fine but long term reliability could be affected.

[ZTZ1010]

Originally Posted by bimmer456

I already said it could handle more but that is what they will cover with warranty. You can tune it all you want with jb4 to over 400 horsepower. It might be fine but long term reliability could be affected.

Right and your assertions about warranty coverage are also incorrect. There is no power threshold above which they will deny coverage. It depends on a number of factors, but saying "if you tune your car they won't warranty any trans issues" is categorically false. Please stop spreading misinformation about tuning and warranty.

[bimmer456]

Originally Posted by ZTZ1010

Right and your assertions about warranty coverage are also incorrect. There is no power threshold above which they will deny coverage. It depends on a number of factors, but saying "if you tune your car they won't warranty any trans issues" is categorically false. Please stop spreading misinformation about tuning and warranty.

If you break your trans and they find a tune they will deny coverage you are implying you can tune it to 1000 horsepower and if it breaks they will cover it that would be false.

[ZTZ1010]

Originally Posted by bimmer456

If you break your trans and they find a tune they will deny coverage you are implying you can tune it to 1000 horsepower and if it breaks they will cover it that would be false.

It's not worth arguing on an Internet forum about.

You said if you tune your car above the MPPSK level that they would deny warranty coverage on anything trans related.

That statement is categorically and unequivocally false.

It depends on the dealer (some are more mod friendly) as well as the specific part that failed. I personally know multiple people running various tunes across different platforms (N54, N55, B58, S55) who have received trans related warranty work on a tuned vehicle, including new clutches.

[bimmer456]

Originally Posted by ZTZ1010

It's not worth arguing on an Internet forum about.

You said if you tune your car above the MPPSK level that they would deny warranty coverage on anything trans related.

That statement is categorically and unequivocally false.

It depends on the dealer (some are more mod friendly) as well as the specific part that failed. I personally know multiple people running various tunes across different platforms (N54, N55, B58, S55) who have received trans related warranty work on a tuned vehicle, including new clutches.

Ymmv with dealer claims have been denied for far less. It depends on if they think the part failed as a result of the tune.

[GF]

Originally Posted by bimmer456

Ymmv with dealer claims have been denied for far less. It depends on if they think the part failed as a result of the tune.

The bottom line is you're only certain of warranty coverage if you don't tune. There's a reason dinan offers tunes that come with an additional warranty
I personally wouldn't risk my warranty for a tune.

[eluded]

This arguing on the Internet is funny. BMW has said the MPPKSK is tuned for less torque in the manual transmission because of the limits of the transmission. So I think that statement would be correct.

Say you blow a motor, If BMW finds out you modified anything at all on the car your powertrain warranty will be denied.

[rockymtnpilot]

This was going to be a really informative and useful thread until you clowns showed up

[BLACK HAWK DOWN]

Okay, the short answer is nobody knows, unless;

a) someone got the info from inside BMW
b) someone strapped up a few boxes and wound them up until they blew up
c) imperical data from tuners that blew boxes
d) someone ran a hunch of boxes for hours and thousands of kms at different hp/tq levels until they blew

So something that wouldn't be easily known.

What the forum will tell you is, what hp/tq levels hasn't resulted in a catastrophic failure.....yet.

[vcx]

Hey, I am also interested in this old topic.

I contacted ZF and here is their answer:

"Die Bezeichung des Getriebes wird bei der Konstruktion des Getriebes vergeben. Das angegebene Getriebe GS6-45BZ ist nominal für 450 NM ausgelegt, kann aber z.B. durch Aenderungen in der Stückliste auch für eine mehr Drehmoment hergestellt werden.
Die genauen Angaben kann Ihnen jedoch nur der Fahrzeughersteller liefern, denn er bestimmt, welche Motor/Getriebe Kombination im entsprechenden Fahrzeug verbaut ist"

In summary, the base model of that gearbox is build to stand 450 NM of torque, but the car manufacturer can specifically ask to support more torque.

So in the end, only BMW can answer if the gearbox in the manual 340i can endure more torque or not.

Is there a BMW mechanic here that could check it ?

[vcx]

bump!

Any info concerning the max. torque that the gearbox and clutch can bare ?

Anyone having troubles with the 6MT after tuning the engine ?

[joeyb26]

Originally Posted by vcx

bump!

Any info concerning the max. torque that the gearbox and clutch can bare ?

Anyone having troubles with the 6MT after tuning the engine ?

My clutch started slipping after a BM3 stage 2 tune with downpipe. Getting the 550i clutch installed which is rated to hold more power and torque

[vcx]

Originally Posted by joeyb26

My clutch started slipping after a BM3 stage 2 tune with downpipe. Getting the 550i clutch installed which is rated to hold more power and torque

thank you for the input.

I get the clutch slip thing, but I am more concerned with the gearbox itself, that would be very expensive to change if it breaks..

Any issue in your case ? How many miles do you have since the tune ?

thank you!

[joeyb26]

Originally Posted by vcx

thank you for the input.

I get the clutch slip thing, but I am more concerned with the gearbox itself, that would be very expensive to change if it breaks..

Any issue in your case ? How many miles do you have since the tune ?

thank you!

I haven't had any gearbox issues no, I do know a few people on here who've also had clutch issues. I haven't really heard of anyone with gearbox issues.

My car has 19,000 miles when I bought it, I put the tune (BM3 stage 2) on with about 21,000 miles and it started slipping almost right away and progressively got worse

Which is odd because my old 340i xdrive that I leased new, I had JB4 stage 2 on for roughly 20,000 miles and never had one issue