Rear End Swap- Good, Bad, And The Ugly

[zibzer]

So my little v6 woke up this morning expecting a set of 3.73 gears and a posi. but after 8 hours of work ended up with no Posi and howling 373's

 

basically the posi I had was for the OBS trucks so couldnt use that. and when the mechanic got the gears installed they howl like a b*tch at ~50mph.

 

The good side of the story is the 3.73's woke this v6 up. Still not V8 quality but much nicer than stock 3.08's. Get up and go is a bit better and itll hold OD on anything. I took a trip i usually do and noticed on the hills it used downshift to 3rd or stick to the edge of OD, it actually held OD like it wasnt going up anything at all. I dont know why GM used 3.08s in the first place, maybe gas milage, but ill find out the difference soon enough.

 

Shittiest part is i thought the whole swap would cost 500 (parts/labour). looks like if i want it it will cost close to 1500 or more.... my mistake, live and learn

[bigredmariner]

3.08's are great for mpg's and not alot else. The 3.73's are nice and you will notice a difference in power and a little difference at the pump, but you can't always have it both ways. The "howling" is most likely due to inappropriate backlash between the ring and pinion. I can't quote you specs on this since it's been several years since I've built a rear-end, but maybe some of the other members will chime in and give you some tips.