Going to change to a 3.73 rear end my car currently has the 3.23's i need to know what all ill need exactly. So any information will be more then helpful.

 

Are you doing it yourself? I had mine done at river city differentials in sac. It cost me $425 but took off 3 tenths and the car feels much stronger. If you are doing it yourself, you should get a master rebuild kit and fluids of course.

 

when i had mine changed out all i had was the ring and pinion and the shop bought new bearings for it. it cost me $220 for the install. i checked out this one place and they said the bearing would need pressed....don't believe it!! they were gonna charge me $380+....they just buy a new bearing when installing the gears...i have 3.73's too and they're awesome!

 

Im doing it myself just need to make sure exactly what to order from richmond.

 

Yeah don't get motive. I've heard too many horror stories about whining and such. And make sure you break them in. 500 miles at only 20 minutes per run and then dump the oil and refill it. You will see metallic shavings in the oil. After break in, mash it all you want. Mine gears are GM and I can't here any whine at all even though I have no interior.

 

Richmond is not known to be a good gear set. Doing a search on this board will reveal as much. Motive is actually a very good brand. They actually makes GM's gears.

I would not recommend installing them yourself. You will need a backlash dial indicator, a bearing puller and a bearing press. Very expensive equipment. All can be had at http://www.ring-pinion.com (great guys there!!!).

You will have to find the correct pinion depth, backlash reading and your gear pattern must be proper as well. Installing gears is very much a trial and error process and will require you to remove and install the parts several times until it is just right. Each time you remove it you have to adjust the shims until the backlash is just right (as I recall the backlash reading should be around .008 or .012 - something like that). After the backlash is right you test the pattern by applying a marking paint on it and then rolling the gears a few times. When you look at it it will show the pattern. Your gears should include a picture of what a good pattern looks like.

 

Oh, I forgot to mention you must have access to a torque gun that can supply up to 400 lbs of torque so you can crush the crush sleeve or you can get a crush sleeve eliminator.

 

Like i said im open to all suggestions i got a puller will have a machine shop press the new ones on, as for setting the backlash my good freind has a dial indicator for it, as for the crush sleeve eliminator, im not at all familiar with that can you give me some more info on it?

 

Really. I guess they didn't break the gears in properly or got a bad install job done. Sean at River city diffs is very good. I'm 100% satisfied with his work.

 

Basically it's a solid ring you insert in place of the crush sleeve. There's no crushing needed and it's supposed to strengthen your rearend. I've never used one so I'm not really speaking from experience. I've never heard of anyones crush sleeve failing. It basically makes installation a little bit easier. Try visiting the Strange Engineering website or Moser. I think you can see them on their websites. It's been a while since I've looked into them so I don't recall who carries them. Try www.ring-pinion.com

 

hmm...interesting things being said...i rebuilt the rear on my third gen wihtout and special tools...just had a machine shop press the bearing...and you DO need that have the old bearing taken off the old pinion to get to the old pinion shim...all rear end pinion depths is set for the specific case, so setting pinoin depth is not required unless the old gears are just worn out...all you do is swap the pinion shims. backlash can be set using only the marking compunds and lookin at the pattern...it takes a lot of time, i think it took me about 4 hours to get an acceptable pattern, there is a .002 tolerance that MUST be met, do not settle for more that this, do it right the first time. i used the $124 motives, and they hummed, but i was told that unless they are exactly at there spec, they will hum, even if they are within the .002 tolerance, and they were 4.10's, so that didnt help the humming, but as long as they dont grind, ide say you are alright with it. total, it cost me $450 including the posi i installed it was about 140 for the used posi, 124 for the gears, 100 for rebuild kit, and 60ish for the spacer i needed...as for the crush collar i took a 6 foot metal poll on the end of a breaker bar, and tighened that thing down as tight as i could...my mechanic buddy told me it would be okay that way, so i did it, and havnt had a problem with it, it had 6k miles on the rear when i sold the car, and it was fine the entire time...best money i spent on that car

my point is, it can be done without special tools, i had never done it before this, as long as you are careful, and take your time, it will be okay...the most important thing is to have the pinion shims swapped out, because setting pinion depth is very difficult without special tools...and very time consuming, you have to make a dummy pinion bearing, and use old crush collars...no fun...it took me a total of about 10 hours to do the entire thing...which isnt bad considering how much i would have paid someone to do it otherwise...good luck and let us all know how it goes!

 

Will changing the gear and doing the rebuild kit help at all with the strength of the rear end? Will you have to get a new posi and a strengthened rear end rebuild kit? 1994CamaroZ28 I don't know if you are just upgrading the gear or upgrading the whole rearend and I was just wondering if the suggestions about the rebuild, posi, and new gears would help increase the strength of the rearend.

 

Good point about the dummy bearing. That will make installation easier. I don't know if I would ever try it without a backlash setting. I just wouldn't feel comfortable driving it. A backlash dial indicator is pretty cheap. Mine only cost about $50.

 

for the most part, all these 7.5 inch gears are equally weak...and putting a posi in, or changing ratios will not significantly change rear end strength...actually it will make it more prone to break with a higher ratio, there is more torque exerted on the axles, and the teeth of the gears...if u want to strengthen your rear end...buy some strait cut gears (very loud...the noisy m-22's were noisy baucause they were strait cut), strange axles, and a rear end cover with bearing supports...or do a ford 9" or gm 12 bolt swap...or mabye even a mopar 8 3/4"

 

Not really. You can get a differential cover and add a little bit of support to the bearing caps but that's about it. If you're upgrading to a 3.73 or 4.10 you're actually putting in weaker gears as the size of the teeth is considerably smaller (the lower the ratio the weaker it gets). The added strength of a 12-bolt or 9" comes from the increased size of the ring gear. The larger it is the thicker the gear teeth. They also tend to have stronger axles and other components for increased strength as well.