373's or 410's?
 

Ok, here is my dilema.After a lot of diagnosing the noise in the rear of my truck I have finally found out what it is.Pinion bearing or bearings.I was hoping for a wheel bearing or carrier bearing as they are much easier to change.No such luck.My friend at the dealer told me I might as well change out the ring and pinion because they have over 70K on them.I have 410's in there now and am not very happy with them.I have 255/70/16 tires.Originally I had 225/70/15's with 355 gears.I don't really want to go back to the 355's because I know it will be a slug(more than it already is) but I don't like the 410's on the highway.I am at 3,000 rpm at 80mph.I have the 4.0 OHV so it doesn't like to rev like a SOHC.That leaves me with 373's.Does anyone have a combo like this and if so how do you like it.One of the main reasons I want the 410's out is that it really didn't help the truck as much as I thought it would over the 355's.I even ran it at the track and it didn't make any difference,maybe even slower.My truck has never gotten good gas mileage and I wouldn't expect it to improve much but every little bit helps.I do about 70% city driving and 30% highway.

4.56. :dunce:

lol!

Hey, if you're unhappy with the 4.10's on the highway, and losing a bit of acceleration/take off torque doesn't matter, 3.73 sounds about right to me. Doesn't that take you back to the effective ratio of a 3.55 with your original tires? Close, I should think.

slow down, why the hell are u going 80 on the highway anyway?

Because...he can. :wink:

The posted limit on I95 down here is 70, and the average speed of traffic is between 80 and 85. I routinely cruise at 82-83mph myself.

thats crazy, shows how often i get on a crowed interstate.

I was gonna say, 3k RPM @ ~80 MPH sounds LOW! .. But then I've got the SOHC, 4.10's and ride 31's..

W/ my combo I don't like to exceed 70 MPH EVER, on account of very poor gas mileage. I actually cruise at 65 (our posted limits) a lot if I'm not in a hurry. Doing so, and shifting under 2k RPM in town (read: driving like a grandma!) is letting me nip at 19-20 MPG..

If you're not happy w/ the 4.10's, and weren't w/ the 3.55's for the opposite reason, sounds like 3.73's are the only thing really left. Unless your'e willing to condisder taller tires..

Up where you live, the term "crowded interstate" is an oxymoron! :wink:

heh, that and the highways u need to be skilled at high speed manuvers to avoid the pot holes :wink

i concour with the rest, 3:73s will set ya in the desired range. but remember higher (4:10s) will yield better gas milage in stop n go traffic...

I would think it would be close.Maybe someone who is much smarter than me could figure out the final drive ratio taking into account tire size.I do remember it drove pretty good with the 355's but with shorter tires.I don't recall it feeling like the engine was going to explode and shower a passing minivan with hot oil when cruising at 80mph like it does now!

using a generic OD ratio of .80, a mph of ur standard 80 mph a 3:73 gear with ur 255/70/15 (around a 29" tall tire) yields about 2750 rpm and a 3:55 yields 2500...