s-10 rear end swap

[timw48030]

Ok its been a while since I have posted anything.I have a ? maybe somebody can help with does anybody have a complete list of parts you need to do a s-10 rear end swap to a monza houseing useing a 3.42 posi with 28 axels? what year s-10 to look for that have the 28 spline axels and the right length axels ? Iam also looking for a 3 series posi carrier NO gov loc crap.


Thanks Timw48030

[rickhunter1max]

It is possible to use just the axles, ring, and pinion from an S-10 rear end with some changes to different bearings. Instead of using the whole rear end from an S-10, you can also just use the axles from an early '80's 2wd S-10 You can only use 2-wheel drive Chevy S-10 and Blazer axles for a 5-lug upgrade. The axles are the same spline (26 spline) and are only 1/16" shorter than the stock Vega axles. This makes a 5-bolt swap easy. Grab the larger drums and backing plates from the S-10 as well. Besides being larger, they are often finned (better cooling) and some of them are aluminum (lighter). This swap will only work with '76 and up 7.5" rear ends.

In some cases the shorter axles result in the rear brake drums (also 5-lug) rubbing against the rear backing plates (dust covers) around the edge where the drum meets the back cover. The backing plates may have to have about 1/16" shaved of the lip facing the drum to prevent rubbing. Mine do not rub, but if you find that yours do just remove 1/16th inch from the edge of the backplates. To do this, I would suggest scribing the backplates 1/16th inch in and using a handheld grinder, remove the excess metal. Then smooth the edge with either a file or sandpaper. NOTE: 1975 and earlier vehicles have 9" diameter by 1" wide brakes and therefore a smaller backing plate. Later model (1976 to 1980) backing plates will be required for this modification.

The 7.5" Chevy S-10 gears will fit the H-Body case, but the main problem is that, in the differential case, the hole for the pinion bearing is smaller in the H-body differential than in other GM 10-bolt differentials. You can either get a machine shop to enlarge this hole or use a special pinion bearing and race.

You’ll need; S-10 gears, S-10 posi unit (if it’s posi), and S-10 axles (2 wheel drive only!) S-10 rear end yoke, S-10 drums (if you use the S-10 axles). If you reuse the Vega axles, check if the carrier of the S-10 is a 26-spline unit. The S-10 pinion gear requires Timken bearing #16143, Timken bearing race #16283, and National seal #8610, S-10 pinion yoke, and "Combination" U-joint (Dana #5-3022X). As with most all gear sets a specific gear carrier is required for a specific range of gear sizes, so the carrier must be the correct series for the gear set that you want. In other words, you need to know what series the carrier is or what gears were installed on it from the factory. A 2-series carrier fits 3.08 and numerically lower gears (3.08, 2.93, 2.73, 2.56, and 2.29), while a 3-series carrier fits 3.23 and numerically higher gears (3.23, 3.42, 3.73, and 4.10). The exception to this is if you purchase custom gears specifically made to fit your specific carrier (i.e. you can buy 3.23, 3.42, 3.73, 4.10, and 4.56 gears to fit the 2-series carrier). If you are at all performance minded, you will probably want to have a positraction unit in your H-Body. Stock posi rear ends for these cars are actually quite abundant, but can sometimes be pricey. You can upgrade to a new or different posi carrier by getting a 26-spline carrier of the right series for your gears Auburn also makes an aftermarket posi unit for the 7.5" rear end as well. Also, the Camaro and S-10 7.5" posi unit will fit the 7.5" H-Body rear housing. I have had a posi carrier from a Camaro 7.5 rear installed in my H-Body rear since 1988 and it works fine.

So, the list is:

* Enlarge pinion hole in differential and use S-10 bearing, race, and seal
-OR-
Use these non-factory parts:
Timkin bearing #16143,
Timkin bearing race #16283, and
National seal #8610.
* 7.5" gear set with pinion
* New carrier if the new gears won't fit your current carrier (see 3.10)
* S-10 rear end yoke
* "Combination" U-joint (Dana #5-3022X) to mate the S-10 yoke with your stock driveshaft

NOTE: Installing new gears requires setting the proper pinion depth and carrier position. Doing this wrong will destroy your gears. Even the most die-hard shade tree mechanics leave this to a professional. If you want to try it anyway, this is the basic procedure and tips from Robert (twelve_second_vega): "When you pull the carrier, mark the shims on the side of each bearing. They are cast iron and must be handled with care. Put a new crush sleeve on the pinion and install it in your 7.5" housing. Set the preload (about 10 inch pounds with used bearings) and set the carrier in place. Gently tap the shims you took out into place with a PLASTIC hammer and torque the caps. Only once did a gearset need to be reset. 99% of the time, you can just throw them in and go. If the backlash is off (.005" - .008" with used gears) you will need different shims. Subtract the amount you need (in backlash reduction) from the right shim to move the ring gear deeper into the pinion. BE SURE to add this SAME AMOUNT to the opposite shim. You MUST maintain the preload on the side bearings. When properly set-up, you will have to pry the carrier out of the housing and putting shims back in should not be easy either."



Ring/Pinion Swap Specs



(Turn the S-10/F-body pinion down .060")

H-body pinion O.D. (rear bearing): 1.3755”
(front bearing): 1.1875”
S-10 pinion O.D. (rear bearing): 1.975”
(front bearing): 1.1875”

Cover gasket: Victor #P2782 (NAPA) or Fel-Pro #55072
Bearings (axle): JM14070 (?); Torrington DB67309; NAPA R1563-TAV
Seals (axle): NAPA #13992
Bearings: (pinion, front, H-body & S-10): NDH #M86649A; John Deere AR94761
(pinion, rear, H-body): Timken #HM88649A
(pinion, rear, S-10, stock): Timken #HM89249
Races: (pinion, front, Buick & S-10): HDH #M86610CJ
(pinion, rear, H-body): Timken #HM88610A
(pinion, rear, S-10, stock): Timken #HM89210

Seal (pinion): National #8610
Differential carrier bearings: Timken #LM501349
Differential races: Timken #LM501314

[timw48030]

Hey thanks for the reply but thats not the info that I was looking for,the info that Iam looking for is the info about useing 28 spline axels and what year s-10s to lookfor with 28 spline axels that will work in the monza 76-80 7.5 houseing. I want to build my owen rear end with a 3.42 series 3 carrier with 28 spline axels .



Thanks Tim 48030

[NixVegaGT]

Looks like any 7 5/8" S10 pickup '88-'98. Also look for a 7 5/8" (7.625") carrier. You can also use series 3 gears with a series 2 carrier and a spacer. Just in case you are having trouble finding one. Another option is to get a so-called "weak" torsen from the late camaro/firebird guys. They swap those out for tougher stuff. Works great in our lighter cars though.

Good luck.

[Fastone27]

Hello all. I'm new to the forums but knee deep into converting mine over using only the 26 spline 5-lug axles Mine are from Moser and are a duplicate of the S-10 axles being 1/16 shorter. But i know I'm over-thinking this but are the bearing and everything the same ? I only need to change the bearing if I'm using the S-10 ring and pinion along with the S-10 axles correct? Thanks Guys.. Help a newb out!I will introduce myself along with pics of my 72 as soon as i can Its going to be a pretty nice ride!

[Fastone27]

Hey Guys Not sure if these answers are for me but i have run into something else that is strange now After taking out the ring and pinion in my rearend the new Moser ring pinion i ordered for it are different The pinion that came out is a 25 spline pinion and the new pinion is 27 spline Any help in what i actually have would be much appreciated What i have believe i have is a 76-77 Monza V8 rearend with torque arm. If you need more info I can see what i can get. Just FYI I purchased the car with this rearend in it aleady so i really am at a loss

[Monza Harry]

You should get a hold of Jim (Monzaz) on the board here, that is his business and he races a nice Monza. So he will be able to fill in the blanks, the rest of use may leave. The Monza (and cousins) rear takes a special pinion shaft size not shared by the F&G-Body, and S-Trucks, and again Jim is your guy, I believe he is the only supplier that has these on the shelf, (the only one I know of anyway). Harry (he also sells on eBay http://www.ebay.com/usr/monzaz http://www.ebay.com/itm/v8-Monza-Vega-4 ... 1614942057 http://www.ebay.com/itm/V8-Monza-Vega-3 ... 1593370445 )

[hammerdown7]

Does the torque arm mount with 4 short bolts or two long bolts? You may have a later 6.5 rear axle instead of the 7.5.

Dick

[TimMcCabe]

FYI,

The S10 backing plates will not work with the Monza/Vega housing.. it mounts differently and also has the wrong offset.
I found out the hard way when I swapped out the S10 housing I had in my Vega for a 75 Cosworth diff. I wanted the big brakes, but the S10 plates would not work, so tragically I had to convert to rear disk brakes

Cheers,
Tim

[Diesel Dan]

I'm going to look at a 2wd 1998 S10 blazer and check the rear axle.
I already bought the front brake assemblies for $70 and checked the glove box and it has 3.42(GU6) gears and the G80 locker.
Need to crawl under it and see if it has the 7.5 or 8.5 axle.

[Diesel Dan]

Even if it is a 7.5" I'll probably buy it anyway.
My 4wd blazer has an open 7.5 so I could install it there.
Already have another 3.42 blazer rear with disc brakes but it is a 4wd housing so there is another open carrier I could use.

According to my math 3.42s with 24" tires will give about the same effective ratio as the 4.10/31" combo in my trucks.