I will get flammed for this.....

I put mis-matched rusty Gm stamped 4:10 gears with two chipped ring gear teeth in mine for fun one saturday. I had about 6 track passes and 1k miles of street driving then I drove it to Michigan from Florida. I went thru "Tail of the Dragon" and then all highway the rest of the way. I left the car there for about a year then just drove it back to Florida this week. It whines so loudly at 52-64 you think its about to blow up and has a high pitch scream at 70+. I can say that I was completley rolling the dice and going out on a limb but my mis-matched (ring and pinion not from the same set - huge no-no) gears were set up right and havent blown up yet. I think the biggest aspect to this argumment is the set up and driver. More importantly the driver, I know I could go out tonight and do launch after launch until something broke but I perfer to be slighlty smarter and understand my weaklink rear.

Is it stupid to sink alot of money into your 10 bolt......ABSOLUTLY but for a free set of gears a $100 install kit and a few hours of my time I love the results. Lets be honest with ourselves, everything we do and talk about to these cars is a waste of money but we all do it anyways.

Just my .02 and story.

 

I bought my car with the 4.10's already installed @ 20K miles and the rear whined like crazy. I made about around 20 1/4 mile runs with street tires and about 50 runs with M/T 275 40 drag radials. Best times were in the 12.9's @ 109 mph and 1.9 60 ft. times. Also ran about 20 Autocross events. This was over the last 2 1/2 year period and the car now has 28K miles.

The rear started to make more noise than usual, so when my buddies asked me to go to the drag strip, I said sure. After the 1st run, I was unsure if the rear was getting louder. After the 2nd run, I was quite sure something was broken or ready to break as it was knocking. I had 1 more buddy to line up against and when I ran the 3rd run and hit 2nd, bang, knock, knock, knock. I thought the rear end was coming apart. Everything somehow stayed together and I had it towed home, (gotta love AAA 100 mile free towing). The next day I pulled the cover and found 4 broken teeth off the ring gear and a cracked Torsen thrust block.

I personally decided to fix the 10 bolt and save up for a MWC 9" with Watts link for the future. I do not want to add the unsprung weight of a 12-bolt, Dana 60 or stock 9". I went with GM 3.73 gears and bought a used TA cover to hopefully get me through to Jan. 2012, when I will have enough saved to correct GM's largest mistake with the 4th gen f-body. I know the $700 spent is just a band-aid and I will only drag race a few runs next year to see the difference in the 3.73 vs. 4.10. I do more autocross now anyway and for me this was a good compromise.

It is just a matter of time with a stock rear and 4.10's in a 6-speed car. Good luck.

 

In short if you have good money get a better rear to handle the power, If money is low repair the original and dont beat on it(as much ) til you can replace it.

 

Well I had my 10bolt rebuilt with 4.10s in April of 09. I didnt even make it to the track but I did have some good fun with mine on the street with some spray. And then over the winter I did a new clutch and sent the M6 out to be freshend. Well guess what, the ole 10bolt started making some bad noises, so I said screw it and put in a Moser 9inch with a locker and 4.11s. I got a good deal on it used and finally made some all motor passes at the track. Ill tell launching at 4500 with Nittos and shifting the **** outta it the rear doesnt even flinch. Best money Ive spent. PERIOD. Do it once man trust me I was in your shoes for awhile but its worth the wait.

 

I have busted 2 sets of 4.10 gears and have come to the conclusion that the ring gear teeth are too thin. I don't recommend gears lower than a 3.42 in a 10 bolt.

 

yup i broke stock 3.42 on street tires with less than 10 track passes and broke them on the street just putting around. then my 4.10s just broke recently on street tires again with about 3 track passes on them once again broke on the street just cruising

yeah i'm going with the s60..even strange will tell you its a better rear end and its cheaper than the 12 bolt but about the same price after having to buy a driveshaft

 

I had 4.10s in my stock 10 bolt. Worked perfect until I took it to the track with the converter. The stock **** Zexel broke. Fixed it and put an auburn pro series in it. Drove fine for a while. Numerous track passes and it ended up breaking the auburn just turning sharp in a parking lot. Gears never got hurt tho.

 

Last week I broke my 10 bolt with 3.73's. Car didn't move 10ft. from the launch!

 

I was running 4.10's in my 10 bolt for about 5 years and about 200 track passes on ET Streets hitting low 13's to mid-12's. It's all about how you drive the car. I would never launch higher than 2500 rpm. Sold the rear intact and got a Moser 12 bolt with 4.11's and launched that bitch at 6000!

 

Driving style does have a good amount to do with longivity..
Doing your burnout and NOT allowing the tires to chirp whenn finishing the burnout helps....

I also would say,most automatic owners have been more successful with 10bolts. the ET streets help cushion the impact aswell....
As for us 6spd peeps its more difficult and there is NO timeline for a 10 bolt 4.10s and sticky tires hell some break them on radials lol

GM FAILED in the rear end dept. since 1982,the bean counter that attempted to save money was a TARD! Owell thank the aftermarket for some dependable rears.....

 

Mine was a 6-speed before. I switched to auto and went 373 for nitrous. I forgot to mention that I would granny shift to save the tranny. Bottom line is 4.10's with a 10 bolt will work but you gotta baby it. But there's nothing like launching at 6000 rpms with a heavy-duty rearend!!!

 

I did here, not the gears tho they held up great, just the axle broke in half. F the 12 bolt go 9 in

 

Thats the truth.. exact reason why i am doing my 8.8

 

I'm on my 5th rear . 3 in 1 year on drag radials. The last 1 broke just driving down the street. I'm currently on street tires and that's the way I race. Riding the clutch out a bit is definitely less destructive than a high rpm clutch drop. I could've invested in a 12 bolt a while ago but I never intended on racing this car this much. My lt1 is/was my track car.