Rear gears

[cgarb]

Not really an engine problem, but it's caused by engine HP...lol. I have an 8.8 Ford rear in my Buick Skylark drag car. This is the 2nd set of gears that I have cracked the teeth on the ring gear. These are very small cracks, the teeth aren't broken, I just can notice the rear making noise when coasting up the return road. I have used Ford Motorsport gears, all 3 sets that were in there. The 1st set lasted like 9 seasons or more, then when I upped the power to my 377 it cracked a few teeth and I heard it growling. So I replaced it with the same 4.56 Ford Motorsport gears and upped the power again to a 421 and raced it for 2 seasons and it has cracked them again. These gears are being set up by my Father who is a Ford mechanic who has worked at the local dealership for at least 40 years. We use the Ford tools to set up the pinion shims and backlash to spec. They pattern perfect and are dead quiet when new. My question is is there a better brand of gear that I can use that are stronger and will last longer?

[pdq67]

Don't have clue!!

But I have to ask why you didn't install a 9" under her instead of the 8.8"??

pdq67

[cgarb]

Because I was 18 and poor and that's what I had. I had a rear out of a mustang that got sold with 33 spline Moser axles and a spool, so in it went. Originally this car was built to run. 11's to get me by till I could build something better. Last year it went 9.90's with my 421. This car weighs 3200lbs race ready. I feel the 8.8 has done pretty good for what it is.

[cgarb]

Now I'm 38 with children and a house payment and still poor...lol

[travis]

Sounds like it may be time for some softer “race” gears, rather than the harder “street” gears.

[cgarb]

That's what I'm looking for, but I can't seem to find any in an 8.8 in 4.56. The Pro gears, they are 9310 alloy right?

[dazimm531]

I have had good luck with US Gear. Do you run a cover with the bearing supports?

[cgarb]

Yes, bearing support cover and a solid pinion spacer.

[Abbottracingheads]

That is why they make Pro Gears. They are softer and dont crack light street gears.

[pdq67]

Thank you for your reply back to me.

I understand, "use what I have"!!

And with my three little ones.

Have a nice day.

pdq67

[cgarb]

That is basically what I'm asking? Does anyone know a company that makes a 4.56 Pro gear for an 8.8 Ford? I can find them for Dana, 9" and 12 bolt. What were the Pro 5.0 guys running back in the day? They had to use 8.8 rear and had way more HP that I can muster.

[travis]

That's what I'm looking for, but I can't seem to find any in an 8.8 in 4.56. The Pro gears, they are 9310 alloy right?

Yes, I believe they would be 9310.

I just spent way too much time searching and the only thing I could find in a Pro gear for the 8.8 was 3.90’s

There is something out there called a “lightning” treated gear that is supposed to be longer, harder, faster, etc...but it’s still an 8620 material.

Very strange. I guess it’s just expected that you move up to a 9”??? There used to be pro gears available for the 8.8...not sure what happened there

[cgarb]

I called and spoke with Strange Engineering this morning on the phone and he said the same thing, no 9310 or "Pro" gears are available for the 8.8 Ford. He said their go to gear set is a US Gear ring and pinion. I have a set of those in 4.56 on order. Hopefully I will have better luck with that. I do need to do some upgrades here soon, looks like a bulletproof 9" will be one of my items on my wish list.

[allencr267]

Is the best contact patch the best for power as well as quiet, different contact at the inside/bottom/root of the ring and any cryo snake oil testimony?

[BigBro74]

Is the best contact patch the best for power as well as quiet, different contact at the inside/bottom/root of the ring and any cryo snake oil testimony?

I was wondering kind of the same thing. I have abused and broke a few 8.8 gears sets my self in my 85’ carbed gt (yes I installed a Motorsports housing) 5.0- it was not nearly as powerful but a five speed and a much younger me with nitrous was very hard on the equipment. I feel like the last set of Motorsport gears I installed(4.10’s) before I sold the car held up the best- pattern was okay but NOT heavy toward the root of the teeth and I had the backlash right on the widest spec- installed redline gear oil I think- it had just a very light whine at 40 but didn’t puke- sold to a guy I knew and he didn’t have problems either but he never used nitrous and was a bit more conservative drive than me. I probably only made about 30 passes with it after I did the gears that time.