AWD conversion

[Andrewcoja]

You can spend all the money you want and it will never work as well as a car that came from the factory with AWD. I wouldn't even want to convert a 3 series to AWD.

[Edogg218]

The hard parts and fabrication are the "easy" part...as others have said, wiring and software will be the real challenge. I feel the only people that would do something like this have bottomless pockets.

[tracer bullet]

You're getting resistance on this because 99.99% of the people that ask about converting a car to AWD (one that never had it as an option to start with) never actually go through with it.

You could be that .01% that does, it's possible, but without knowing anything about you, and without you seeming to know anything about what you're asking, you have to understand the skepticism.

[flinchy]

so much hardware, so so much

would be pretty cool though.

[Freon]

It would be pretty epic to have an AWD 135i, but what everyone else said.

My guess would be transplanting an entire 335xi AWD drivetrain is your best bet. Entire engine (longblock), transmission and PTU, front diff, front axles, front driveshaft, suspension knuckles, possibly other bits of the suspension (??), possibly the even front subframe, ECU, and wiring harness. More like a 135i shell on top of a 335xi. You'd need a custom rear driveshaft, probably the correct rear diff to match the front diff drive ratio (probably the 335xi rear diff itself, hopefully fits).

I'm not sure you'd want to actually rewire. Taking the whole harness and ECU from the AWD car might be more practical. Wire loom locations and routing might be an issue.

Who knows what sort of issues there may be with the steering rack, too...

Anyway, it would be cool. Could be the ultimate STI/EVO killer for quadruple the price...

[Mit_Boost]

Originally Posted by ThatOneKid

I'm looking to see if 335 ix parts would fit on a 135i. But actually thank you I'm sure that will be the most useful advice that I get. This is why I never post on this forum because like you said its for general enthusiasts who only ask what exhaust is best and have probably never picked up a wrench/ have no actual car knowledge.

Can it be done, possibly? Anything is possible at the right price. I'd recommend first checking the wheelbase widths (135 vs 335xi) and then checking clearances in the engine bay/underbody for all the AWD system you're gonna install (transfer case, front driveshafts, Xi subframe, etc). You'll probably want a chassis specialists to make sure that you have mounting points that will work. So confirming every possible measurement is your first step.


If that works out, it gets difficult --- Gonna assume you'll try to pickup a "salvage" 335xi (otherwise you might as well sell your 135 for a 335xi) and hope that there's no damage to the drivetrain or electronics. You're going to need the 335xi's entire wiring harness for the XI sensors/traction control programming/etc.



IF the spacing works out and it can be fabricated, it's probably gonna be close to $30k (between the actual fabrication and parts/salvage car you'll need) without any unexpected problems.

Originally Posted by Zombie1

What the s65 swap run you? I've only seen it done once and they didn't have the cost.

G-Power has done it and that sounds about right. A motor swap is pretty simple to a drivetrain conversion.

[Dieselboy]

Originally Posted by ThatOneKid

Alright, pretty simple question. Is an all wheel drive conversion possible (135i)? I realize this would be pretty expensive, but the alternative for me is to buy another evo IX, or I suppose a 335ix but the latter is a good deal more expensive. So I guess I'm wondering if I could take pretty much every part I need from a 335 ix +a small bit of custom fabrication? Or would this be a totally custom job and hence completely unreasonable? I live deep in the mountains of Colorado and really need a good AWD car (not looking for other car suggestions as I know all of the choices I would be interested in, but this project has always held some interest for me). Any help is appreciated.

Colorado huh? I think you may have smoked yourself retarded. Buy a used Jeep for $5k and use the 1 for what it was intended.

[Dmacc]

Wait for the 235i x-drive

[dd135is]

So,long story short, fully functional e82 xdrive, i have one :-)

there was some issues to build one, half of job calculated as a learning process
but at the end, it`s done and it`s work with all electronic gizmos without any fault codes from ista

base build starts with buying wrecked 335xi, that is only reasonable way to build it because there is shitload of small pieces that must be taken from donator.
i had a crashed 135is build date 09 2017 and a crashed 335ix build date 09 2018 at start point on this project and that age different is was one of the biggest issue.


electrinics is the main issue where i messed most because of not knowing everything and there was not so much information here how to do it but working with TIS, ncsexpert, inpa, ista, etc everything is solveable when you just decide to solve it.

PS, i should change my nic to DD_E82_135ix :-)