I think my transmission just exploded.

[Kroggers]

Took the car out for her second drive for this year, after all the work I did this winter on her interior etc I was feeling really happy with the car - and then everything just turned up-side-down

As I shifted from second to third, there was a nasty bang followed by a metal against metal banging sound. I killed the engine and pulled into the side of the road to investigate.

All looks OK from the outside, and the engine starts and runs with no problems. The clutch feels OK as normal, and I can shift between the gears. But the gears are not engaging at all. When the car is moved I get the same metal against metal knocking sound which is coming from the transmission area...

Not a fun way to start the Porsche season

My heart is foolishly hoping this is a cheap and relatively simple fix like the clutch, but my head is saying trashed 915 with a heavy rebuild cost!!!

Any thoughts out there from the experts?

[Davewjunior]

Have you taken a look underneath the car yet? Any holes/leaks in the transmission case? I had nearly the same thing happen to me a few months ago. Turned out that the left axle had come off of the transmission and was hanging. The "bang" was the shaft hitting as it swung around. Cost me about $280 to fix (shaft, bolts and LOTS of Loctite). I hope it turns out to be a cheap fix for you.

[Kroggers]

Nope, not been under the car yet - I need some time to relax and build up energy to fix it...
I did have a look under the car when it happened, and could not see anything unusual.

[Hodgey]

you sort of have to get really way down and look back up towards the transaxle output to see if the shafts have come off or not....

[Walko]

If it is the axle make sure you replace all the bolts on both sides otherwise it will let go again. As I found out more than once.

Michael

[john walker's workshop]

sounds like a broken cv joint or an axle fell off.

[Grady Clay]

Here is the definitive thread on this subject:

Reconstructing Constant Velocity (CV) Joints

While long, this thread is worth serious study.

Best,
Grady

[gtc]

That sounds like what happened when one of my axles failed. The splines on the axle which hold the CV joint in place were rusted, and the CV joint slipped and stripped off the splines. I was getting ready to drop the engine and tranny before I finally noticed that a wheel was moving while it's axle was not.

[Kroggers]

Thank you all for the good replies. I decided to stay away from the car yesterday as it was just making me upset, and we had planed a nice family bbq for the afternoon.

I got up early this morning with a fresh mind ready to investigate, and as you have all already predicted - my transmission is fine. This is what I found as soon as I lifted up the rear of the car and had a closer look



I cleaned and repacked my CV's when I did the suspension work 2 winters back. I did the installation as defined by Porsche and checked them again twice during last year to make sure all was good, so this reay took me by surprise...

[village idiot]

Did the bolts shear or did they just back out?

My 914 did the same thing. Turns out the bolts backed out(I had just put the engine and trans back in after a top end job).

I drilled and safety-wired the bolts after that incident

[Sigurd]

Should there not have been washers and plates under the bolts? Are the bolts of the correct quality?

[skinnerd]

Been there for sure.
When it happened to me on a crowded freeway in rushhour traffic, it was not a fun experience.

Cruising at about 65mph in heavy traffic, then a big bang....followed by a terrific amount of noise in the back.
Oh yeah, and the engine was revving to the moon (throttle linkage was all torn up under the car).
Somehow I got the car over to the side of the road....coasting because I killed the ignition almost immediately.
The flailing CV put a huge gash in the SSI, sheared off the throttle support on the side of the gearbox, and mangled a number of other things it could get it's hands on.

For me, it was a pricey incident.
Hopefully, you have a lot less damage.

[curoswiss]

Exact same thing happened on my SC and two of my friends SC's... Great motor though :-)

[Kroggers]

They backed out. As far as I can see there is no real damage done.

One irritating thing is that I have the Stage8 locking CV bolts on order - Wish I had received them and installed them before now!

Obviously I will have to remove the axle and clean it all up. This is one of the jobs I hate the most, so I will use this as an excuse to get myself new axles and be done with it

I have the car booked in for a full alignment and corner balance next Thursday which I do not want to cancel. I also will not be able to get the replacement axles and install them in time, so my plan is to just put it all together limp to the alignment and limp back home - park up the car and hope I can get the axles delivered and installed (with the Stage8 bolts) before my first scheduled track session

I am just glad the transmission is all OK!

[Kroggers]

Originally Posted by Sigurd

Should there not have been washers and plates under the bolts? Are the bolts of the correct quality?

Hard to make out on the picture, but there are washers there. These are the correct bolts, as ordered from our host when I did the work last winter...

[Davewjunior]

Glad it's going to be a "cheap" fix for you. When I read your thread, that's exactly what came to mind. I had used the correct bolts when I a did a repack and the CV boots this winter. I guess I must have gotten a little grease on the threads as I put them back in. I just used a little Blue Loctite on the threads after cleaning them for the reinstall. Now I get under the car at least once a week and check the bolts on both sides (probably should have been doing that in the first place). I'm thinking that the safety wire idea may be a good one.

[Kroggers]

Yes, in theory it ended up a lot cheaper than it could have been.

But as I have now convinced myself to purchase two new axles rather than having to go threw the cleaning and grease packing project from hell again, it will cost me a bit more

Having had this experience, I am now really glad I decided to order the Stage8 bolts. Just wish they would have been delivered on time and not been delayed - as I would have already swapped the bolts out by now.

[wildcat077]

I think i'll go spend some precious time in the garage today and re torque my axle bolts !
I replaced all four rubber boots last Summer and installed new bolts from our host but after reading this post i'll put the odds on my side ... lol

Cheers !
Phil

[ToddM]

This happens quite a bit, just be glad you were just cruising around and not into some real spirited driving at the time.

After any CV joint work, it is good to re-check them after the first drive.. then in a week, then in a month. I still check it yearly as part of a normal inspection.

[Kroggers]

Wow, I have just meet Mr. Porsche Tax and he was not a nice person

As I said, I will be replacing both my axles for new ones like these from our host for $267.75 - I would order them from Pelican if the shipping to Sweden and the import tax would not make the end price so high.

I have found a supplier locally that can supply them for 3152SKr (that's $434 in your local money). Now I know this is close to 50% more than from Pelican, but still cheaper once you calculate in the shipping etc to Sweden.

But here is the shocker! I decided to contact our local Porsche centre to see what the price would be from them - as they are close and I could collect! How does just over 12000SKr each sound to you - yes that is $1650 a side!

I pointed out to them the price from Pelican and the other supplier I found in Sweden, and the answer I got back was "can not be original Porsche parts, the quality is probably not as good as the ones we supply"... I am shocked!!!