Finally found a guy thats done this stuff for 13 years and he seems to know his stuff. He kind of talked me into 3.92 over 4.10, just for gas reasons i suppose. He said he will use sierra gears and a posi that dont use clutches. He has me at 1100 parts and 300 labor. This is just 2wd. What you guys think, are sierra good ? He also bragged himself up and said not to worry about a whine noise, cause hes good.

 

I am not sure what exactly you are doing but if you are just looking for gears you can get them for around 200 bucks. $300 for labor is about average.

 

He may be talking about a True Trac, it uses worm gears instead of clutches . That price isn't too bad for the whole carrier, including gears. Never had one but they say it's quieter than one with clutches so you should be okay if that's what it is. There are two kinds, make sure it's not the locker which is much cheaper and not as freindly to use.

 

He gets his parts from california. He said the clutch limited slip is $300 cheaper. Also 3.92 gears are $100 more then 4.10s. I know 1400 sounds high, but he said his labor is only around $300. Now i just have to decide which gear to go with. I dont tow anything, its strictly for more get up power.

 

3.92s are a good upgrade from what you have, but at 80 mph they would yield about 2/10 of a MPG worse gas mileage than 4.10s according to my tire rotations per mile calculation and would go down as cruising speed decreases from 80. But that little bit of extra gearing may be the difference in the tranny staying in gear and searching for the right one in certain situations. If this is for OFF THE LINE performance only the numerically higher the gear, the better. 4.10s will get off the line faster than 3.92s, 4.56s faster than 4.10s and 4.88s faster than 4.56s.

His price is high and again like in your last post - YOU NEED TO KNOW WHAT LSD HE IS USING.

PLUS I am very familiar with Yukon, Precision, Genuine, Richmond & Motive gears and IN EVERY CASE the 3.92s are the same price as their 4.10s (and 4.56s for that matter).

Edit: I just did a search on a couple of my 4x4 specific forums and there is a little bit on the Sierra's. One guy says his 4.56s are noisy as hell (but this is probably a poor install). According the the Sierra website, they don't make a 3.92 for a Chrysler 9.25" rear but they make a 3.90, the difference in negligible.

The few places I can find that sell them list the same price for Chrysler 9.25" Ring & Pinion sets from Sierra from the 3.21s right on up to the 4.88s, so I don't know why he is charging you $100 more for the 3.90s over the 4.10s.

The most I can find on them is on the Jeep forums, the gist is they are bargain priced gears with prices rivaling the Chinese made stuff, but they are US made. They advertise US quality gears rivaling Motive at the price of "bargain" gear sets.

They are $200 gears, allow $100 for the install kit. IF he's using a true Detroit TruTrac then the going price for that is $500, so I come up with $800 in parts and I'm going retail, I'm sure he's buying wholesale. I dunno what clutch type LSD is $300 cheaper because the only other one I'd use is an Auburn and it's $400 ($100 cheaper).

In my experience, a mechanic who brags about how good he is, isn't for sh*t, but he might just be that good.

Find out SPECIFICALLY what LSD he's using. Be sure you are ok with the 3.90s and ok with over-paying for his supposed expertise cause that is about a $1100 job in my book WITH a DETROIT TRUTRAC.
GET EVERYTHING IN WRITING, if he's as good as he says he is, then he'll have no problem spelling out that if they whine in the least, he'll make it right at his cost!

Remember, after all is said and done, YOU are the one spending the money here. If you want certain brands and ratios it's your right to get exactly what you want...

 

Heres the deal. I cant remember what lsd he was going to use, but he said the clutch type were $300 cheaper from the supplier. A company he deals with alot. He didnt recomend them. I believe he did say like 3.90 and 4.11 gears, but said the 3.92 is less demand, so they are higher price.

At first, he said i should go to 3.73 cause that is an overall good gear. Im not sure about this guy. He said his work is gauranteed if i use his parts. I mention moes performance 4.10 july special, and he said he wouldnt cover parts failure. Only if i used his parts.

 

the dang parts would only fail based on his ability to install them right. walk away from that fella..

 

I second the walk away. Hammer knows his stuff, I trust him and what he says. The guy you are dealing with sounds like he is full of it. I myself wont let some normal guy install them no matter how much experience he has. Mine are Yukon 4.56's with Timken bearings getting installed by a company up here that all they do is gear and axle work so the work is guaranteed. The prices should not be any different based on demand of them, that is BS. This guy seems to be feeding you a bunch of junk in hopes of you believing it all and him able to screw you around. I would shop around a little more and hit the actual shops that specialize in that kind of work that can guarantee everything and put it all in writing. Once you shop around, you may just find out that this original guy was blowing alot of smoke!

 

Ok. I appreciate your help fellas !

 

If thIs is your reason for regearing, then go with the 4.10, it is not a cheap mod so do the higher gear ratio.