3.73 or 4.10?

[96z28]

I want to change my gears but im not sure what to get. I know 4.10 would rock on the strip. I'm not to worried about gas because my daily beater truck gets about 10mpg. What brand do I need to get and do I need to put them in myself or get a pro to do it? If i take it to a shop, how much would it cost? Would you get 3.73 or 4.10 if u were me?

[NJSPEEDER]

i usually use richmond gears. never had any problems with them and their customer support is very good.
if you want to do the rear up right there are a few other things to consider as well. get some studs for the bearing caps and a good cast aluminum cover with cap supports. also weld the axle tubes into the housing for increased support.
assuming you have a good carrier already i would say your total would be in the area of $750 with a professional install. figure 250-300 less if you doit yourself.
4.10's are definately the way to go.

later
tim

[smokeum99ta]

4.10s definaly.richmond is pretty good brand.and have someone aka "professional w/ good track record" setup the rear for you,its not hard but theres alot of mistakes that can be made that could cost you more money.it normally costs $200-350 just for the setup ,thats not including gears,gear oil,gaskets,bearings,shims,and what else you might need.

[Rob]

Unless they have changed, Richmonds were very noisy. I went with Motive, which were the gear supplier at the time for GM. Strange is also a good gear. Any of the F-Body vendors would have genuine GM gears.

[VTNewb]

What is a good AutoX gear?

[scotts94_z28]

if your car is A4 id go 3.73's but if its M6 go 4.10's and deffinitly have them professionally installed. Also i heard that motive gears are very good and should be just as quite as stock.

[Injuneer]

As noted above, you need:

-gears. In general, the Motives or Superior are essentially the same as the factory gears. I've seen way less complaints about either of those than the Richmonds. I've had excellent results with US Gear (also sold as Strange), but that's with the 12-bolt sizes.

-an install kit. All new bearings, crush sleeve (you may want to consider a Ratech solid spacer instead of the crush sleeve), shims, etc. Also may incluse the gear lube - a quality GL5, and a bottle of the GM limited slip differential additive.

-The aluminum cover with preload bolts, as described above.

Definitely go with a "pro" install, and as noted, make sure the shop has a good reputation. If you were to install them yourself, you would need a dial indicator, stand for the indicator, and a pinion depth gauge - a bit of an expense. I've been working on my own cars for more than 40 years, and if there is one thing I wouldn't attempt to do myself, its set up gears.

Now.... as you can see..... by the time you get the gears, install kit, cover and pay the labor on the install, you are looking at maybe $750. You can get a 12-bolt for $2,000-2,500 and it will be bullet proof, at leact until you reach the 1,000HP level. And, its a very easy self-install, particularly if you get the Strange, which comes fully assembled, filled with lube, and run in at the factory.

I had a complete setup for my 10-bolt ready to go - got it for a good price from T. Byrne on a group purchase, but after thinking about it, I called Tom Byrne and we cut a deal where I'd ship the 10-bolt stuff back to him, and he'd sell me a Strange 12-bolt..... one of the best moves I ever made.

[Master of Stiks]

I'm with injuneer, 12 bolt is the only way to go...unless you go with a Ford 9" which is the best, the only thing that ford has done right since Henry died.LOL Anyway as to the gear ratios, 4.10 is great for low end, and you will definitely feel the power, however it will lower your top speed, and kill gas but you said you did not care about that so...go with it for drag. 3.73 is great for power but retains most of the fuel economy as well, better highway gears. Of coarse you could go with bigger than 4.10 if you want real power, I wouldn't suggest it unless you are planning on just having a drag car though.

-Stiks

[Rob]

I disagree about 4.10 lowering your top speed. With the stock 3.42 gears, top speed is in 5th as 6th will slow down in the 130's because of the high(lower numberically) gear. With 4.10 gears, 6th can now be used as a pulling gear and you will achieve a higher top speed.

[Injuneer]

I'm with Rob.... you will not lose top speed with the 4.10's in a 4th Gen M6. You will simply need to shift to 6th gear to achieve it. And you will not lose significant gas mileage. With the double overdrive gears, it simply makes 6th gear a lot more friendly at lower road speeds.

[FireFinder20]

I disagree about 4.10 lowering your top speed. With the stock 3.42 gears, top speed is in 5th as 6th will slow down in the 130's because of the high(lower numberically) gear. With 4.10 gears, 6th can now be used as a pulling gear and you will achieve a higher top speed.

Well, i was lucky enough to go with 3.73s, 4.10s and 4.11s (Ford 9") in my 93 6 spd Formula.

My radared(?) top speed with the 3.73s in 6th was 162 (previously 157 with 3.23s)

When I went to the 4.10s and the 4.11s, I could barely break 150, but my 60' went from 2.1 (stock), 1.9x (73s & MT Comps) to a 1.6x (MT Comps)

All in all from my own personal experience with the gears, the 3.73 is a better all around gear, but nothing gets your blood pumping more than choosing to start a race from 1st or 2nd gear and kick ass like the 4.10s


by the by, as far as the noisy Richmonds (that was my gear of choice at the time), a little fricition modifier from the GM parts counter does the trick.

[96z28]

its an a4, would the 4.10 be to low for an a4?

[FireFinder20]

4.10s are usually the way to go with an A4

[Injuneer]

its an a4, would the 4.10 be to low for an a4?

Helpful hint.... include usefull info like the tranny type in your "signature", so people can answer your questions accurately, without guessing. That info would be a lot more valuable than the stuff about your beater and the "Honda" stuff.

[Kevin - Blown 95 TA]

If he has an A4 in a street car with a 10 bolt, I think he should put in a 3.73. If it is a track only car, then he might be able to use a 4.10.