holy crap, i chopped my rear axel off!

[jetboy]

for those who don't know, i've been struggling with tuning and high rpm troubles--

I just finished some adjustments - and took it out for a spin around the area - to get to high rpms i got to stomp on it - its emeryville- kinda industrail, no ones around at night, but the streets are short- lots of stop signs.

so I pulled hard off a stop sign, punched it, and Kathump! my right rear axel sheered the bolts off right at the differential!

Everything else looks fine- a clean cut right through every bolt-

i didnt even know that was possible--

does this mean the differential went as well?

[rogerspeed]

I've had the same thing happen with a different car with rear half-shafts (Alfetta sedan). Chances are the bolts failed because they were not torqued properly and/or were not the proper high strength bolts (metal fatigue could also be in play). The diff should be OK, the car won't move under its own power because one side of the diff is spinning. Get new high-strength bolts with nuts and torque them properly.

PS - It wouldn't hurt to check the other side, but most of the power from a standing start is on the right side.

[jetboy]

yeah, thats what I was hoping--

-- it just surprised the hell out of me. damn glad it was only a block from my house. might just bring it in and have it done professional like-- seems like it might jsut be worth getting it on a lift and doing it right-

local bmw shop is fing expensive tho - on the other hand they do handle a lot of 2002s - so they know what they are doing at least

[Zenon]

for those who don't know, i've been struggling with tuning and high rpm troubles--

...

so I pulled hard off a stop sign, punched it, and Kathump! my right rear axel sheered the bolts off right at the differential!

That's torque, baby! Must be doin' something right. ;-)

[GetOuttaMyWay]

Nice work man, looks like you're putting down some monster HP

I'll be parting out an e21 on my driveway Saturday, you should stop by. Got some homebrew on tap too.

[albawhore]

Hey I've got that T-shirt.

Most likely they were just loose and the diff is fine.

OSH for 12.9 cap screws, a good quality torque wrench and some loktite = a good life.

Cheers

Justin

[steve k.]

been there, done that

like the discussion about the strut bolts, the axle bolts will suffer fatigue if they are loose. Check them regularly. I think they only get loose on one side, but i cannot remember which

steve k.

[albawhore]

DRIVERS,

EVERYTIME.

JB

[winstontj]

This is an easy fix if you can get the old bolts out on your own. Just order the BMW parts and you will be fine. Buy an allen 1/2" drive socket and use a torque wrench to torque the fasteners properly. Someone will have to chime in the proper numbers as I don't own the blue book...

Easy & no need at all for you to go to a pro.

A word of caution is to check the CV boots though. If they cracked open during your mishap you will need to fix that prior to driving on that output shaft. THAT is a messy job and may be best to a pro.

[bimmerboy]

where should they be replaced?

[albawhore]

High and anywhere that you put consistently high loads on them.

The higher the torque that is called for in the repair manual the more you have to worry.

In critical load areas in the electrical industry we check every fastener with a tourque of more than 20 ft/lbs on a Bi-annual basis or twice a year. To the point of measuring the fastener for nominal length.

This is in situations where a failure could literally mean $100,000 a minute, but you get the point.

Chers

Justin

[winstontj]

where should they be replaced?

IMO just don't re-use things like this. Anything important like output shaft bolts, head bolts, strut housing to steering arm bolts, etc. are not worth the risk. New OEM fasteners are cheap (compared to a failure) and it makes the job go way easier with new parts.

Be mindful of the things you are going to send out to be plated. Some things should be considered a one-time-only use.

[prsncat]

Hey, if you are parting out an E21, then let me know what you have. Especially if you have:

1. An excellent dash

2. Rear lenses and side marker lenses?

Anything else worth getting?

Brian Foster

Irvine CA

[jetboy]

Nice work man, looks like you're putting down some monster HP

I'll be parting out an e21 on my driveway Saturday, you should stop by. Got some homebrew on tap too.

i am afraid its probably just old car and average hp-- and a little too much hot rodding off a stop!

that said, i dont think the solex phh hurts-> when it works it works really well

awsome-- id be happy to lend a hand and drink your beer-> sucks i probably wont be able to bring the '70 unless I push it---

[jetboy]

got new bolts -> 10 bucks for 6 OEM bolts plus lock nuts (ps: there are two types, long bolts with lock nuts, and shorter bolts that attach directly to the shaft. - lucky mine were the bolt type - i dont think you can get the other type out if you break them off!)

- so a pretty cheap problem - as long as installation goes well.

probably gonna do the otherside as well, but wanted to fix this one first and see how much of a pain in the ass it is.