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I am about to do a gear swap on my 91 pickup as cheap as possible with as basic of tools as possible. Bring on the neysayers! If you are brave enough.....follow me into the mists of Avalon! I am going from 4:10 to 4.88 as cheap as possible. I have never done this before but have done just about everything else. I hope this helps someone or at least shows them what not to do. Here is how much I have in it so far. This is just the rear 8" axle for now.
R&P $113.00
Master install kit $94.00
Gear oil $21.00
Borrowed puller from my friend.....priceless.
I have a press and calipers and a small machine shop in my basement so I will save some money by not having to buy some of those tools. If I mess it up and it blows my rear after the first 50 miles then I guess I get to do it again. I have shied away from this job for years because of mystique that surrounded it. I always thought that only old guys with thousands of dollars of tools and decades of experience could do this. I'm sure they are lights years better than I will be at this task.......but you have to start somewhere.
Here we go.
I pulled the axles.....I really like the removable 3rd member! Much easier than my jeep to work on.
Axles out!
Crusty Axle housing... This axle laid in my yard for 9 years before i used it.
3rd member out
Punched the bearing caps
My gear oil wasn't very old but it looked nasty!
Slimy Crush sleeve!
Carrier...
That diff has been rebuilt once before, that is not an OEM pinion seal.
Carry on.
I thought the same thing when I saw the green goop.....So I asked my buddy.... PO of the truck and he said he replaced the seal when he bought the truck back in 99.... So i'm guessing the pinion drag was not properly re-set. But the wear on the gears look fine. I have another diff I could have regeared but it has a welded diff in it....I loved it off road but this truck is my dd now so I used the rear with the open carrier.
One question i have is......do you guys re-use the locking tabs on the ring bolts? the instructions with the gears did not specify. Thanks!
so.....the new crush sleeve in my install kit is .045 shorter than the old one!??
I always re-used the locking tabs.
Just curious how you got the ring gear over the carrier? I always set it in a water bath in an old electric skillet, monitoring the temp with a temp probe and a DVM.
Then the ring falls right onto the carrier and you can easily spin it to get the bolts installed, just gotta work fast before it cools.
You need more shim on the pinion. This is where a setup bearing comes in very handy.
My ring gear tapped on easily with a rubber hammer. I wish I had a setup bearing but i do not have one and I had to cut the cage of the old one to get my puller on it.....I am going to get a bigger puller tomorrow so I can pull the new bearing off to add more shims.
You probably know this, but a few tips on the flange when you're installing it for the final time:
Put a little bit of RTV on the pinion splines before installing the flange. This will keep oil from leaking up through the splines and oozing around the stake nut.
Use red threadlock on the stake nut, looks like they gave you some in your kit.
Put a thin film of RTV around the outer edge of the seal before installing it into the housing. Just another potential source of an annoying leak.
A basic diff holder makes things sooooo much easier. This is what I use, it's crude, but it works well. You can also see my homemade spanners for the side adjusters. The "Y" shaped one is for doing e-lockers.
Thanks for the tips! Yes I need some type of diff holder..... It is a pain having it rolling around while working on it.
Looks good to me. I would run it. See... that wasn't so hard, was it?
Go very easy on it for the first 50 miles or so. It will run hot. Eventually the gears will get happy and you can start going a little harder on it. Change the lube after a few hundred miles, don't be surprised if it looks like silver paint.
Yeah I am happy with it... It was challenging but very rewarding! Not hard. Now I just have to install the seal and sleeve and set the pinion drag and put her back together!
Here is a picture of the shim I made.... It brings my sleeve up to 2.440. thoughts? I dont have a solid spacer and the new one that came with my kit was shorter than the one I took out.
Did you try the crush sleeve like it is? It's been my experience that the bearings in the kits are "fatter" (if that makes sense).
It's harder than you think to crush those sleeves, you will need something VERY stout to hold the flange and a long wrench on the 30mm socket. I have a piece of 2x2 x 48" angle steel that is drilled at one end for a pair of the flange bolts. I clamp it to my workbench (that is bolted to the wall), then put a cheater on my breaker handle. Still... I swear I'm about to have a stroke sometimes trying to get that thing to crush.
I got a little time to work on the diff tonight.... I spent about an hour making some stuff that made my life much easier! I made a jig to hold the flange while I crushed my sleeve.
It wasnt nearly as bad as I thought. Once the bearing pressed on I felt it get really hard and then i could feel it give once the sleeve started to crush then it turned hard but smooth. It took forever but once all the slop was out of the bearings I would tighten the nut about a 1/16th of a turn then I would check the Pinion preload then I would put it back in the jig and go some more. I did that about 15 times until I got it right. I really wanted to make sure I didn't go too far and have to get a new sleeve. It wasn't bad at all. Then I popped the carrier in and started setting the back lash. I am a little unclear on how to set the preload on the carrier bearings without changing the BL. I set my BL to .008 then I snugged up the adjuster wheels until they were tight.....then my instructions say to turn the wheels 2-2.5 holes then torque the bearing caps to 58lbs. Does that sound right?
Flange holding jig!
Adjuster wheel tool so I can use my torque wrench.
Nut "dinged" and red lock-tite.
Well.....its all back together. I topped off the oil and went for a little drive. No weird noises. The case was a pretty warm to the touch but I hear that's normal. I will give some more updates on the performer once I get it out on the open road. Thanks again for all the help.....and don't go anywhere because I'm sure I will need some help with the front.
Thanks guys for all the advice and for following! I took the truck on my normal commute today. It makes a big difference. 5th gear is more usable than ever. It still is a 30 year old truck with 82hp, but it is enjoyable to drive now. With 33's and the 4.88s the speedometer is very close to being accurate now. indicated 55mph, GPS confirmed 53 mph. 5th gear at 65mph looks to be around 2850rpm.....or so. My tach numbers are very hard to read.
