'08 335xi sedan power risks

Crookracing31 · 06-02-2014, 09:51 AM

I have an '08 335xi 6at, sedan. It has some great performance upgrades. Probably 400-425hp range. Never dynoed. Running cobb stage 2+ FMIC. Also have the alpina trans flash.
Just had to replace a failed trans case. I'm worried about what will fail next? Anyone with similar mods had issues with other drive train parts or the tranny going prematurely?
What can be done to increase reliability in these parts? Any help/comments/feedback? Are there companies out there that can rebuild drivetrain parts that can handle this added power?

ajsalida · 06-02-2014, 11:55 AM

Have a similar car and mods, no issues here so far. Lots of folks running far more TQ/HP thru XI AT's and not blowing stuff up (yet). Guy just posted up in this section an 11.5 sec 1/4 mile running RB's with XI + AT and Alpina. Seems to be hit or miss.

I am wondering if people who live in mountains and/or see a lot of snow aren't having more issues with TC's going out. Also seems most bad TC's are really just the worm gear on the electric motor gets chewed up. Not the clutches inside or metal parts. At least that is my impression reading here in the XI section.

Another thing is people seem to be finding ugly fluid inside when they change it, it is supposed to be lifetime but then so was my first marriage and a lot of other things in life. Also a TC adaptation reset feature which I still don't know if you can do via INPA or not. Have not changed my TC fluid yet (or AT for that matter) planing to do all diffs and tranny at 50k miles. Currently 38k.

stashtrey · 06-02-2014, 07:57 PM

Sorry to hear about the t case. Care to share symptoms leading up to failure/replacement?

Dosturbos · 06-02-2014, 08:35 PM

What will fail next….Everything.
I have replaced damn near everything except for injectors, transfer case, and motor.
You name an issue I've had it.
owning a tuned 335i is so love hate

spinall4335xi · 06-03-2014, 04:46 PM

front diff failed. FBO

Carl Morris · 06-03-2014, 10:28 PM

There is a shop in Colorado Springs that would like to see your transfer case if you still have it and would want to send/take it to them. They mostly do GTR transmissions now but would be willing to get involved with our drivetrains but haven't seen a failed one yet.

AWD Addict · 06-04-2014, 03:19 PM

How many miles on the OP's car?

Crookracing31 · 06-05-2014, 02:45 PM

Quote:

Originally Posted by AWD Addict

How many miles on the OP's car?

81k.

06-02-2014, 09:51 AM	#1
Crookracing31 Private First Class 68 Rep 119 Posts Drives: 2008 e92 M3, 2016 F85 X5M Join Date: Mar 2014 Location: Draper, UT iTrader: (1)	'08 335xi sedan power risks I have an '08 335xi 6at, sedan. It has some great performance upgrades. Probably 400-425hp range. Never dynoed. Running cobb stage 2+ FMIC. Also have the alpina trans flash. Just had to replace a failed trans case. I'm worried about what will fail next? Anyone with similar mods had issues with other drive train parts or the tranny going prematurely? What can be done to increase reliability in these parts? Any help/comments/feedback? Are there companies out there that can rebuild drivetrain parts that can handle this added power? Attached Images
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06-02-2014, 11:55 AM	#2
ajsalida Colonel 226 Rep 2,387 Posts Drives: 95 M3, 02 R1150GSA, 09 335xi Join Date: Aug 2010 Location: SW USA iTrader: (2)	Have a similar car and mods, no issues here so far. Lots of folks running far more TQ/HP thru XI AT's and not blowing stuff up (yet). Guy just posted up in this section an 11.5 sec 1/4 mile running RB's with XI + AT and Alpina. Seems to be hit or miss. I am wondering if people who live in mountains and/or see a lot of snow aren't having more issues with TC's going out. Also seems most bad TC's are really just the worm gear on the electric motor gets chewed up. Not the clutches inside or metal parts. At least that is my impression reading here in the XI section. Another thing is people seem to be finding ugly fluid inside when they change it, it is supposed to be lifetime but then so was my first marriage and a lot of other things in life. Also a TC adaptation reset feature which I still don't know if you can do via INPA or not. Have not changed my TC fluid yet (or AT for that matter) planing to do all diffs and tranny at 50k miles. Currently 38k.
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06-02-2014, 07:57 PM	#3
stashtrey Lieutenant Colonel 294 Rep 1,834 Posts Drives: 08 E90 335xi TiAg Join Date: Dec 2012 Location: Sacramento, CA iTrader: (8) Garage List 2008 E90 335xi Sedan [0.00]	Sorry to hear about the t case. Care to share symptoms leading up to failure/replacement?
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06-02-2014, 08:35 PM	#4
Dosturbos Lieutenant 55 Rep 467 Posts Drives: 2017 F48 X1 MSport Join Date: Mar 2012 Location: Medford, MA iTrader: (1)	What will fail next….Everything. I have replaced damn near everything except for injectors, transfer case, and motor. You name an issue I've had it. owning a tuned 335i is so love hate
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06-03-2014, 04:46 PM	#5
spinall4335xi First Lieutenant 19 Rep 376 Posts Drives: 08 335xi, Silver, M Sport. Join Date: Feb 2012 Location: Denver iTrader: (1)	front diff failed. FBO __________________ 08 E90 335xi, M Sport, 193M wheels, S1 coilovers, stop tech rotors, Bren tune on E80, 7" FMIC, Catless Downpipes, afe intake, B3 Flash. "When the turbo's spin the bullshit will end" Team Spin All 4
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06-03-2014, 10:28 PM	#6
Carl Morris Captain 19 Rep 650 Posts Drives: 2008 335xi 6MT Join Date: Feb 2012 Location: San Jose, CA iTrader: (0)	There is a shop in Colorado Springs that would like to see your transfer case if you still have it and would want to send/take it to them. They mostly do GTR transmissions now but would be willing to get involved with our drivetrains but haven't seen a failed one yet.
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06-04-2014, 03:19 PM	#7
AWD Addict Chief Executive 300 Rep 2,886 Posts Drives: 2008 335xi 6spd Coupe Join Date: Dec 2007 Location: Boston iTrader: (1) Garage List 2008 335xi [0.00]	How many miles on the OP's car?
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