used ring and pinion... opinions needed

[droptopford 5 0]

i have been under the impression that ring and pinion gears are pretty indestructable, but i now face a situation where i can get a used set of 3.73's for free. they are Ford Racing 3.73's taken out of a 650+ HP hatchback. the guy who offered them to me said i could have them for free, then we just talked a little bit and agreed for him to install (parts and install kit for $300.) I was wondering if i should have second thoughts about receiving this set of gears with the high HP... it wouldnt be worth it for me to pay for teh install and have something let go on me so maybe it IS too good to be true. BTW, the guy who is giving me the gears owns his own speed shop and is very knowledgeable. thanks for the opinions, Kyle P.S., if anyone has recommendations for an aftermarket trac-loc differential, throw them out there for me to read... i was thinking eaton over auburn gear?

 

[The Green GT]

If they are FRPP then they should be good. I got my gears new and most people will say to stay away from used ones, but if they were installed properly the first time and are installed right when you get them you shouldnt have any problems. And for free. You can beat that.

As far as diffs go, get a 31 Spline from www.buyfordracing.com and get some moser or superior axles for it. Then you will never have to worry about the rear end again.

 

[droptopford 5 0]

i dont think new axles are within the budget right now...unfortunately. the only way rebuilding the rear-end is within budget is becasue it includes the word FREE in part of it. however, like i said if its not 100% recommended, then maybe i'll have to pass until later... but GAWD do i want those 3.73's...

 

[BlackVert]

ok here is my take on this ...

i had a convertible 1996 gt before this one, and i had 4.10s put in. the 3.27s in there were put in the box and sat in my basement for 2 1/2 years. i just had those 3.27s put in my car (taking out the 3.73s that were in there) and they start whining like a mofo at about 30 mph and up. apparently, what with the way they wear and the limitations on the thickness of the shims that you use to adjust them (so that they fully mesh), it is sometimes not possible to install used gears and have no whine.

my mechanic explained this to me before he installed them, saying that he could 100% guatantee no whining with new gears, and i believe him because he has done alot of work for me (including 2 new sets of gears with no problems at all) and i trust him 100%. if he is not sure about something, he says so.

he also said that used gears that whine when you install them can sometimes stop whining after a while because they wear a little more like new gears and fully mesh after a while.

so i guess what i'm saying is just keep in mind that there is a possibility that these gears might whine after you put them in because of the fact that they are used.

i don't understand it well enough to say why new gears don't have that problem. apparently though, whining (or not) has to do with how well the gears mesh.

in case anyone is curious why i would go back to 3.27s, my motor makes enough torque that it is not going to bog down much when i step on it, and since it is a daily driver type of street car, i'd much rather have the speedo be correct for a change and be able to cruise 70 mph turning 2000 rpm.

 

[trav_19]

ok used gears go 2 ways.....both of my cars have used gears in them....the 93 has 3.73 out of a high hp car that were in it for awhile...and they develop a wear pattern quickly....i have had trouble with it making some noise not bad or anything but its a possibility... my 94 got used gears that were in the car for 3 passes... 4.30's looked brand new he broke the axel and decided to go smaller...lucky me

 

[final5-0]

A N Y set of gears can be hosed ... Big Time

if

Not installed correctly :Word:

It is entirely possible

They could be hosed ... for life

Grady

 

[Methodical]

Get new ones. For me certain things I'd get new and these are one of them. Only thing I'd get used is if (BIG IF) it's something I install myself and is fairly easy to install and remove if the part is bad. But for the most part, I only get new parts.

I don't know about labor charges in your area but I had new ones installed for about the same price. But that was some time ago and labor has risen since then.

HELL - Just Go Get yourself some new gears and eliminate the worrying. Besides, I think that labor price may include some cost for the gears - hidden mind you. Just my perception.

Just One Man's Opinion

 

[94-302-vert]

Spend the few $$'s on new gears...

I had a bad install so my new gears were effectively used when they were finally done right... that took close to 20k miles to get rid of MOST of the vibration/noise.... I still get noise at higher sleeds where I do not drive very often (90+).