[yak]

i am planning a 20 hour round trip this summer to get to a wedding and i want to take my gto. problem is it has 4.10s and an e headed 400 pushin close to 500 ponies. it's insanely loud and revs to high on the highway the way it is. if i can't afford to put a gear vendor od unit in by then i'll have to switch out my ring and pinion to like 3.08 gears or so... what kind of vehicles can i pull a ring gear and pinion and carrier too if i need from? late 70's t/a's? there is a 73 lemans 4 door at the wrecking yard would it be the same? how about from a 10 bolt chev truck?

i should say it's a 10 bolt too....

[Matt Meaney]

70's t/a = nope 73 lemans = nope truck??? = noooo.
a 72 and older 8.2 pontiac buick olds rear will work or a 69 older firebird. chey's 8.2 is different and won't work. (all these are 10 bolts) changing a ring and pinion is kinda involved. imo it would be easier and cheaper to get a whole rear and swap it. at least around here you can find 2.56 to 3.08 drum to drum rears for about $100. my 2c's

[norton70]

yea....just swap out th eentire rear.....than u will know everyting in the unit is ready to go....gear vendor will require some hammer work under the floor boards...are u in the mood to play that game?

[pggto]

Not trying to be a wise guy, but why not use a trailer? I like to drive my car as much as I can, but with those gears and the distance involved you might be $$ ahead to just tow it, and not have to switch out the rear only if your going to put it back to 4:10's.

[yak]

up here where i am it's not easy to find old pontiac buick and olds stuff around here, so maybe i'll just order a new 3 somethin ratio gear set and throw it in. it'll fit on the 4.10 carrier? i'd rather just go the gear vendors od way but $$$$

i think it'll take me just as much time to swap rear ends, if i can even find one around here, as it will to switch ring and pinions around. trailering isn't an option cause i want to drive it out west and back to make a fun trip out of it....

[Matt Meaney]

also not trying to be a wise guy, but if you can set back lash and pinion depth in the car faster than swaping out the rear housing, my hats off to you. if you go with a new ring and pinion, your limited to your choices. i the highest available is 3.55. yes it will fit the 4.10 case.

do you have an auto or stick? if it's an auto, something to consider is the stall speed. you don't want to be cruising at an rpm less than what your stall speed is. this would cause excessive heat in the trans and burn the fluid, possibly ruining the trans. this would also apply to the gear venders unit.

i hope you can get this sorted out and drive the car. no matter where your going, it's always more fun to drive the car there, than trailer it.

have you considered an od auto? they can be built pretty stout. lock up converter allows cruising at any rpm without worry. probably about the same cost, maybe a little less than the gear vendors and i don't think any mods to the trans tunnel required. once again just my 2c's

[yak]

my car has a 4 gear m21 i beleive.... if i remember correctly when i blew the 3.90 gears up and put the 4.10 gears in, it only took i don't think it any more than a hour and a half or so to switch them out.... way easier than dealing with brake lines and bleeder screws and e brake cables as far as i'm concerned to swap the whole housing....

i'm not to interested in swapping over to a 4 speed auto at this time as well....

[engineer]

wow, 1.5 hours to swap ring and pinion, come down to texas, I have several jobs for you to do. 1.5 is what it takes me to swap the entire rear end. and if you use your existing brakes onto the new rear, no e cables or bleeding issues. Come down here, we got lots of drum rears which will fit. could even use the 7.5 setups if just for road cruising.

[Lloyd-TX]

When we overhaul a diff here at my shop, we bill out approximately 6 hours. Usually takes a bit longer than that as we insist on a textbook a backlash measurement and a prefect contact pattern check.

Depending upon the vehicle and the situation, we usually bill less than half of that to install a complete reman axle assembly (usually from Jasper).

[78 GHOST]

IMHO, you should flush the brake fluid once every two years anyway. E-Brake cables are a 5 minute job. Dropping the diff. and swapping another in is MUCH faster, besides you can swap back to the fun gears at the slightest whim without wading through W90 gear oil.

I have everything to do this and I take my time, no where near 1.5 hours.

Your road trip sounds really cool, I kept the 3.08s in my car for that exact reason, with the converter I use, wheel spin is still an issue in 1st and 2nd.

[yak]

Originally Posted by engineer

wow, 1.5 hours to swap ring and pinion, come down to texas, I have several jobs for you to do. 1.5 is what it takes me to swap the entire rear end. and if you use your existing brakes onto the new rear, no e cables or bleeding issues. Come down here, we got lots of drum rears which will fit. could even use the 7.5 setups if just for road cruising.

when i say 1.5 hours i only changed the pinion bearings no side bearings or what not, and lucky for me the original shims worked 100% the first time so i didn't have to monkey with setting it up....plus i'm a shop owner with my own hoist! but anyways i'm gonna look around for a rear diff in the meantime... or the shop's gonna buy me a gear vendors unit....one or the other

[goathead455]

Where exactly are you located?
If you get another diff from a Pontiac you don't have to mess with the brake lines,
pull the axles and take the backing plates off the diff and you don't have to disconnect the brake lines or the e brake cables.
Install the diff with highway gears and put the backing plates on the new diff.
This will only work with the bop 10 bolts.
Also,if you get a cevy 10 bolt there is a good chance your U-joint won't work.

[yak]

i am along the sask/man border, 5 hours east of s'toon, my road trip will take me to sylvan lake/red deer.....

[goathead455]

A freind has 2.56 diff for sale but it is in Calgary.
When you come out in the summer,come up to Edmonton for the friday night drags,only 1 1/2 hours from Red Deer.
Lots of cars usually and a good time.

[yak]

i'm thinkin 2.56 will be too low of a rpm at highway speed, i think around 3.00 would be better,i 'm running a pretty big cam but thanks though ...

[yak]

i've found a complete 3.08 open diff out of a 1968 beaumont for 150 bucks, will the pinion yoke be the same or do i have to swap mine from my original diff?

[getmygoat]

Originally Posted by yak

i've found a complete 3.08 open diff out of a 1968 beaumont for 150 bucks, will the pinion yoke be the same or do i have to swap mine from my original diff?

You can't swap the yoke because the pinion gears have a different # of teeth. However, you can buy a special u-joint that has pontiac on two sides and chevy on the other two.