Differential advice... Any shops in New Hampshire??

StephenB

New member
Although our trip to the Devil in the Dark seemed flawless we have determined that we destroyed 2 ring/pinions over the weekend. At the finish the announcers had been howling at the moon and so was the RX8! After day 1 I complained of a small "driveline noise" which we determined to be the rear differential. Which had my nice expensive 5.12 ring and pinion in it (an $1800 gear!). So Friday night before the Saturday race we swapped it out for a stock spare that we brought along. By the end of the 12 hours it was in bad bad shape howling like crazy. I noticed in the turns that the temp guage (mounted inside drain plug) was bouncing indicating to me that maybe we had a lack of fluid. We thought we had it primed and full and it does not have any leaks so I am unsire if we plumbed it incorrectly or created some type of vacume issue. I have NOT taken the stock rear end out yet but we did take apart my nice expensive one which shows extensive wear to the ring/pinion. So much that it is probably junk :( It also had a lot of backlash.

Anyway, I am looking for advice on what we did wrong. Does anyone know of anyone near Concord NH that may have solid knowledge that could help us out? I can post pictures of the set-up we have and then take it apart and show internal issues as well if someone on here thinks they can give us some advice. We would really like to go to the VIR 13 hr but realistically I don't want to make that tow and not finish without someone saying.. "yup you did this wrong, do this and it will be fine"

Thanks for the help!
Stephen
 
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Do not toss the 5.12, they can usually be saved at least for sprint races. The stock street gear was most likely set up too tight to start with for race duty. Once the heat starts, it just starts self destructing. Does sound like you did not have the proper circulation.
 
Redline MT-90 Before we added the oil cooler we ran Redline Heavy Shockproof and we didn't have any issues. However that can't be used with a cooler...

Stephen
 
He isn't in NH, but, Steve E is THE man for Mazda diffs. As you might already have discovered, he knows them in and out, has all the tools to work on them, and can set you up with everything from tweaked to the nines to stone reliable. Plus he's super nice and helpful.
Use Fed Ex and don't worry that he's not in NH.
 
He isn't in NH, but, Steve E is THE man for Mazda diffs. As you might already have discovered, he knows them in and out, has all the tools to work on them, and can set you up with everything from tweaked to the nines to stone reliable. Plus he's super nice and helpful.
Use Fed Ex and don't worry that he's not in NH.


Jake beat me to it............ Steve is "The Man" for most diffs. Not just Mazdas....... If he can do a Saturn, I'm sure he can do just about anything.
 
I appreciate the confidence guys. I understand it is a sickness and I can't seem to find a 12 step program that does not involve the track. :rolleyes:
 
"Shock proof" may be part of the problem. it builds heat.
I doubt the need for a zero torque small engine. Most shops have moved away from it with cars under 500HP. The Mobil one Gl4 works fine.
You can get the oil to pump with a "out" plug in line with the ring gear. Return the oil below the Out line and it will pump itself pretty nicely. (Keeping the cooler nice and low, and bleeding the air out.)

Yeah, I meant GL 5 also
 
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Redline MT-90 Before we added the oil cooler we ran Redline Heavy Shockproof and we didn't have any issues. However that can't be used with a cooler...

Stephen

Somebody please correct me if I'm wrong, but MT-90 is GL-4. You need GL-5. Tried to warn you but I guess it didn't stick.
 
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