Ring & Pinion failure - G50

[UltimaRich]

Having just received news of my first gearbox problem with my beloved I would be interested to poll any thoughts/causes of R&P failure in G50's.

I had not noticed any obvious noises from the box other than a vibration under load whilst making left turns at pace, hence the investigation whilst having some engine work done.

The car has only covered 5,000 miles and had a box oil change about 500 miles ago ... I am not certain which oil was used but I am investigating to see if this has had an impact.

Any views on likely £££'s to repair would also appreciated.

Thanks

Rich

[peterpsg]

Sorry to hear that Rich.

I just had Quaife install an LSD in my G50/21 and then I refilled it with 3.5ish litres of Swepco 201, 80w-90 gear lube, which a lot of the Porsche guys rave about, and I must admit the gear change is definately smoother now, and the box felt fine up and down the runway on the weekend...

Good luck getting it sorted...

[bigmack]

Sorry to hear about the bad news Rich. What's the torque and hp of the motor?
With so few miles on the G50, I'd question whether it was properly setup to start with. This requires special tools to do properly. One other thing that can happen is that the aluminum diff cover plate can flex, and so most of the guys are upgrading to a billet aluminum cover plate from.
I'm running Swepco 201 in my G50 which is highly regarded in the Porsch Community.
Cheers!
-Mack

[UltimaRich]

Thanks Mack ...

The car is originally a factory built car so I would expect the box to have been setup as the lord intended.

The motor made 550 bhp and lb/ft and is currently in for an upgrade to give it some more revs. My only worry is that the wrong oil has been used as little as 400-500 miles ago which has caused its premature demise.

As it stands I suspect I will go back to the factory for another unit. Should this box need tweaking/modifying before it goes back into the car?

Thanks

Rich

[bigmack]

Since you have the box out of the car and the gearbox guy has it opened up then I would have him change out the 1st/2nd shift fork to a billet aluminum piece from PowerHaus II www.phII.net. This is an item that has been known to bend. I've not had any trouble with breaking synchro rings but some of the guys have changed to steel synchros. While the R&P is being changed out it would be a good time to switch to the billet diff cover which all must be measured and shimmed with the R&P. Check with PHII for additional upgrades. Personally, I'd also investigate an oil cooler and pump for the G50 with over 550hp.
Cheers!
-Mack

[UltimaRich]

I'm glad the Powerhaus site is mainly underconstruction ... it looks like I could spend a fortune

Thanks for the assistance Mack, I am guessing it'll be new box from the factory and possibly a couple of circumspect upgrades ... and the right selection of oil of course.

Cheers

Rich

[bluesatin]

I also use Swepco and never had a problem. Also done aprox 50 standing starts (1st and 2nd gear with racelogic traction control) at Vmax- bruntingthorpe and no problems with the gearbox. Changed the box late last year (LSD and longer gearing) and done a further day at Vmax and no problems! Engin is a 525bhp enforcer with modifications including different carb, a lot of head work (porting) and a wilder cam.

Blue

[B1 ECC]

I had a ring & pinion failure on a brand new factory supplied box, at the time I was using Redline 75-90. In the interim I bought a second hand box and used Miller 75-90 semi synthetic on the advice of Millers tech dept, the box did 5000 plus track miles over 3yrs and never gave any problems. I since rebuilt the original box with closer ratios, ring & pinion, quaife diff, and refitted it over winter. Miller oil--- 300 track miles and no problems!