Okay guy with this weeks paycheck im goin to order a new set of gears, 3.73's 3 series for the 10bolt in my car. I know Richmond is good but i dont know if i could deal with the "whine" they give. what other companys sell good/great gears for the price? Does anyone know what type of gears the GM dealers carry and are they any good? i need to start modding my car again, thanx guys. this is goin to be for my daily driver and this yr will be gettin alot of track use i hope if things work out right.

 

I believe that the Dana corporation supplies GM with gears.

I buy all my gears for Randy's Ring & Pinion. They aren't the cheapest, but the quality is on par with Richmond, but they don't make any noise. The line they sell is called Yukon Gear. Check them out at www.rringpinion.com

 

American Axle & Machine (AAM) makes GM's gears. They sell them in the aftermarket under the brand name "Motive". Dana makes lots of other drive train parts for vehicle mfrs all over the world, but not these particular gears.

The Richmond gears that are famous for whining, are single-purpose drag racing gears. They are made of softer metal (but also more able to flex without beaking) than stock-type gears, to absorb the shock of hard launches; and their teeth are cut differently. The tooth shape makes them whine, and the diferent metallurgy makes them wear quickly on the street. It's a very bad idea to use them if you intend to put more than a couple of thousand miles on them over the entire course of their life. Since you specifically state "daily driver", DO NOT use those gears, unless you don't mind replacing them after what will seem like a very short time.

They are a typical example of a purpose-built racing part, which provides far better service in a racing application than a stock type one, but is unsuited to stock-type applications.

This doesn't apply to Richmond's "street" gears, which are similar to everyone else's good quality ones.

The supplier I use the most is http://www.drivetrainspecialists.com...=28&cat=GM+7.5 You can get just about any of the top-of-the-line gears there, for competitive prices; as well as all the internal parts, various brands of carriers, etc. etc.

 

I had a set of Richmond Gear products in my rear end. They weren't noisy after they broke in (1000 miles). The Competition Gear products were just as loud. The current gear set I have (don't remember the name off hand) is still noisy after 4000 miles. They are starting to get quieter though. I just wish they would quit breaking!!!!

One thing to consider if you have a 7.625" rearend instead of a 7.5" rearend. The 7.5 gears work great in the 7.625 rearend and are half the price........

I've heard the 3.73 gears are less likely to break than the 3.42's. Any truth to that rumor?????

 

7.5" and 7.625" gears are the same thing. There's no difference in strength. You can only buy one kind of gears to replace both of them.

Click on the link and learn some stuff about gears by just looking at the listings.

You can break any ratio if you try hard enough. Personally I can't see how there would be all that much difference in yield strength between the 41/11 set and the 41/12 set, since the teeth are all the same size; there's just one less on the (smaller) 3.73 pinion.

Again, DO NOT use the Richmond drag-race gears if you intend to drive the car on the street. One person's good luck for a short time does not equal "it's OK to mis-apply the parts". I happen to know someone who skydives, and one of the members in his club survived a jump where his parachutes didn't open; does that mean it's safe to jump out of an airplane without a parachute? I don't think so.

 

Is that why GM sells 4.10 gears for the 7.5" and Motives are 4.11?

 

Since GM uses the various series carrier (2,3,ect.) to deal with the thickness of the ring gear their gears don't get a whole lot weaker as the ratios rise, to a point.

4.56:1 is about the highest you want to run from a strength perspective in a GM rear. After this the pinion is very small, and likely to have all it's teeth sheared off under high power applications.

I don't see any strength advantage to 3.73s over 4.10s. You're better off selecting a gear that suits you car, engine, and transmission than anything else.

Often companies sell gears as 4.10s or 4.11s depending on how they rounded during the math required to get the ratio. Typically if you divide the rign gear tooth count by the pinion gear tooth count you get a number that isn't nice and neat like 3.73:1. The gear industry has determined that gear ratios are best expressed by three significant digits, so all ring and pinion sets are rounded up or down to fit into this mold.

BTW, I have also purchased gears, lockers, and axels from DTS and they are hgih quality products sold by a good company.

 

A 9/37 gearset is not a 10/41 gearset because of rounding. Motives are sold as 4.10 gears but are 4.11 (9/37.) GM 4.10s bought in the last couple years by a local guy to put in an f-body were 10/41.

You aren't under the impression that I think before I post, are you?

 

Hmn, that's an interesting tidbit. I didn't think that they would actually vary the tooth count for the gears. Do these sets with different counts still fit the same series carrier?

I have seem a lot of funny things with aftermarket gears over the years. A lot of companies used to sell a 5.13:1 gearset for a Toyota rear that were actually only 4.77s. A lot of 4X4 stuff is like this, particularly with really steep gears. It's almost like the math that determines the ratio doesn't apply. Pretty deceptive if you ask me.

 

BTW, I broke teeth on the ring gear on the first two rearends I broke. The last time I ripped half the teeth off the pinion gear.... I'd hate to think what would have happened if I were running slicks (although my 0-60 times would be much improved).

 

RB thanx for the good info and everyone else. im goin to look at those other sites but probably might end up goin with Jegs, ive bought a crap load of stuff thru them and havent had any problems but im goin to check out the other sites first.

EDIT: Hey RB do u know if that soild spacer that driveline specs. sells is the replacement for the crush coller thingy? and do u think it would be a good/wise choice to get one?

also last question (i think), i scrolled down the page there lookin at gears and how do i know if i need a thick or non thick gears? becuz it says it on a few but the others saying MGGM7.5-373 GM, 7.5 3.73 RATIO , MOTIVE GEAR $175. im guessing those are the gears i want. im not sure if those are for a 3 series carrier.

if u could really help me point me at the set of 3.73 gears i need/want for my car, either richmond, motive or others. but im sure the one i just wrote about up there are the right ones i want.

 

Yes I've used the spaver; it allows you to tighten the pinion nut completely, rather than having to stop tightening when the sleeve has sufficiently crushed.

The thick gears are for putting a 3-series ratio on a 2-series carrier. If your carrier is 3-series (came from the factory with 3.23 gears or higher), you don't need them. IMHO they're not the best choice for that situation anyway; the spacer is a better idea, because then you have standard gears you can use anywhere.

 

does the spacer come with shims so you can get the correct depth and whatnot or is it pre-cut for the correct lenght?

also the gears that i was talkin about 7.5 3.73 RATIO MOTIVE gears for $175 are the correct ones i need? becuz my car came with 3.23 gears and i have a 3 series posi in the rear now, so i dont see why those gears wont work.

 

Yes. You put in lots of shims, and subtract them (or combinations of them) a few thousandths at a time, until you arrive at the correct bearing preload, which is around 18-24 inch-pounds to turn the pinion with new bearings. You'd use slightly less with used bearings (which is what you usually see in shop book specs).

That is of course independent of pinion depth, which you set with a depth gauge and check by the contact pattern. Although, about 99% of the time, if you use a .035" shim with stock type gears, the depth will be well within tolerance. I don't believe that I have ever seen any of these rears come from the factory with any pinion shim other than .035".

Yes, those would appear to be the correct gears.

 

kool thanx a million RB, i just gotta decide between the richmonds from jegs or the motives from dts. gotta check shipping prices. but ill end up gettin the solid spacer from dts

 

well i just ordered everything. orderd the solid spacer and the gears (just hope they are the correct ones). once they get here should be about a month to a month and half before i get them installed.