Jump to content

How-2: Beef up the lowly 10 bolt rear


Krambo

Recommended Posts

Had these pics for some time so I figured a little write up was in order. The GM G-80 and the 10 bolt rear isn't the most desireable combo for high HP/TQ but there are some inexpensive upgrades that will help your rear live a little longer. With the T-case splitting the power on the AWD platforms, the stock rear will be fine however once you combine a stout powerplant, things start to be questionable. Adding a rear end girdle and bearing cap studs provide additional clamping force on the cap and prevent side movement. As the HP and TQ go up, so do the stresses on the rear. For a total of around $250, this is a worthwhile investment for the supercharged, nitrous or stroker guys and lets be honest, it just looks cool :cool:

 

Prior to starting, I would like to reference a great How-2 by Mr P ---> Drain and fill a rear Diff by Mr. P

 

Adding an ARP Bearing Cap Stud kit and a T/A Performance Differential Girdle:

 

1. Drain your rear end gear oil, remove the stock cover (13mm bolts) and ensure the entire gasket material is removed. You may need to scrape the cover mounting surface with a hard plastic knife. I found that brake parts cleaner does a nice job of lifting stubborn gasket pieces. This is also a good time to inspect the stock magnet on the stock cover for abnormal metal pieces. Take a look at the ring gear and bolts and ensure there is nothing out of the ordinary. Check for stress cracks on the gears and the bearing caps. Clean out the interior of the rear with a suitable cleaner and inspect again. If all is copasetic, proceed with the install. This pic is the outcome of this step.

 

DSCN1302.jpg

 

2. Lets begin with the passenger side bearing cap stud install first. Take a 5/8" socket (in my case) and break loose both bolts however only remove one.

 

DSCN1306.jpg

 

3. You now install the ARP stud where you removed the one bolt and torque the stud into the housing at 10 ft/lbs (120 in/lbs). Once the stud is torqued to the propper specs, slip the supplied washer and ARP nut on the stud FINGER TIGHT.

 

A picture of the ARP stud vs. the bearing cap bolt:

 

DSCN1308.jpg

 

A picture of the ARP stud installed in the bearing cap:

 

DSCN1309.jpg

 

A picture of the ARP stud with the washer and nut installed finger tight:

 

DSCN1312.jpg

 

4. Repeat this procedure for the top bolt and then torque the nuts to 60 - 75 ft/lbs. Once this side is complete, repeat the procedure for the other bearing cap.

 

5. Once the bearing cap studs are installed and torqued to spec, take your time and ensure no leftover parts and / or install materials are left in the housing. Again, thoroughly clean the gasket mating surface of the housing. Ensure the cover mounting holes are free of debris. I didn't have the correct tap to run through the holes so I used brake parts cleaner with the little red straw. I inserted the straw into the hole and gave it a blast or two. By doing this, you ensure you get a true torque upon the install.

 

 

CONTINUED BELOW:

Link to comment
Share on other sites

6. On the T/A girdle, back out the load bolts as far as you can without removing them. Install the T/A girdle with the supplied bolts, washers and gasket. If you choose to retain the break line bracket, you will need the longer bolt (if you requested it upon purchase) for the top most bolt. Each bolt receives a torque of 25 ft/lbs. Although not mentioned in the install sheet for the girdle, I chose to torque in a star pattern (like your wheels) to ensure an even seat and torque on the housing.

 

Picture of the back side of the T/A girdle with one load bolt (left side of pic) backed out as far as possible as mentioned above:

 

DSCN1320.jpg

 

Picture of the girdle installed, torquing the mounting bolts:

 

DSCN1325.jpg

 

7. Now its time to torque down the load bolts of the girdle. BY HAND, screw the two load bolts until they make contact with the bearing caps. Take note that your load bolts have indeed made contact with the caps and are not stopped by the Jam Nut. Once you feel the load bolts make contact with the bearing, verify that the jamb nut has not bottomed out on the cover. Torque the load bolts to 5 ft/lbs MAXIMUM. Once you achieve the required torque, tighten the jamb nuts down on the cover to lock the load bolts in place. If you overtorque the load bolts, you run the risk of distorting the bearing caps, creating abnormal wear and premature failure. Take T/A's advice and only do the 5 ft/lbs. :ughdance:

 

Picture of the load bolts being torqued down after finger tight. Note that the jamb nut position. Once the load bolt is torqued properly, the jamb nut is snugged down to secure the load bolt:

 

DSCN1327.jpg

 

8. Home stretch now! While there are provisions on the T/A cover for filling the rear, I chose to use the factory fill location. Open the fill hole on the passenger side front of the rear housing. Add gear oil (75/90) of your preferred brand (I use synthetic Mobile One) until the oil flows out of the fill hole. Install the plug and tighten down. It is debatable whether to utilize the limited slip adder or not so I will leave that up to you. I did NOT use the additive as I feel the synthetic 75/90 is appropriate for this application. Feel free to explore your options.

 

Picture of the removal of the factory fill hole plug:

 

DSCN1330.jpg

 

Picture of a full rear differential prior to re-install of the fill hole plug:

 

DSCN1332.jpg

 

9. Once everything is all buttoned up, take a look for rubbing lines (break lines) and secure if necessary. Stand back and take a look at your new beefed up 10 bolt. Take your truck out and do some slow figure "8"s in a parking lot to ensure the diff is working properly. After your test run, crawl back under for a quick look for leaks. I took this time to add a squirt more oil since the driving coated all the dry surfaces with oil. Take her back out again and get her up to operating temperature, do a final check for leaks, retorque the cover mounting bolts if necessary and finallly enjoy your new upgrade.

 

Some people experience leaking from the drain plug on the T/A cover however I did not. If this happens to you, a simple fix is to use some thread sealant prior to filling the rear with fluid. I took the chance on the machining from T/A to be adequate and lucked out. If I wasn't so lazy, I would have used thread sealant on the drain and fill plug prior to starting this project. You can determine how you want to approach this. :driving:

 

Picture of the installed T/A Rear Girdle and bearing cap studs (not visible,...duh!):

 

DSCN1335.jpg

 

Start to finish, taking your time and having all the necessary tools, an install time of 2 hours is very reasonable. If you bust your butt and do a sloppy clean-up, you can do this in an hour. Take your time and do it right. It isn't a contest to see who is the fastest but rather who's lasts and doesn't leak. :thumbs:

Link to comment
Share on other sites

bitchin' :thumbs:

 

got the part numbers for the arp studs and nuts?

 

 

Sure thing. Call T/A Performance and ask for part # TA 1815. It is true ARP hardware. Around $20 like Chase stated.

 

One other thing to add is that the cover bolts are not stainless and will rust in time. I plan on ordering some stainless hardware from McMaster and installing in the future. :thumbs:

 

I am not a big fan of the Permatex gasket material. If you are not careful and apply too much, it mixes with the gear oil upon install. I just don't feel comfortable having that in my diff when the gasket does the job if torqued correctly.

Link to comment
Share on other sites

  • 1 year later...
  • 2 months later...
  • 2 weeks later...
  • 3 months later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...