View Full Version : Removing pinion from diff housing...stuck

05-08-2004, 05:15 PM
A little OT, but you guys are friggin' smart, so I figure you can help me....

I picked up a Dana D70U at the junkyard to swap under my Chevy K5, but I have to regear it, which I want to do without spending any money for someone else's labor ie., I wanna do it all myself. Here's a cut-and-paste of a post I made on another site, but have gotten no help as of yet.....

I'm trying to do the gears on my D70U. I got the carrier out OK, and the pinion nut off with a long breaker bar. When I tried to pull the yoke, it would not budge. I used a puller in combination with hammering on the back of a 1/2" plate I bolted to the yoke. With a LOT of persuasion, and penetrating oil the yoke came off. Whoever worked on this last ameared rtv around the sealing surface of the yoke, and did not use anti seize on the splines. Inspecting the splnes on the yoke and pinion, there is just enough rust, very light though, but just enough to make them seize. So, at this point, I'm thinking that the pinion should come on out with a little persuasion. So, I placed my lead hammer against the end of the pinion, and smacked it with a single jack. Nothing. So, the smacking began to get progressively more forceful. Well, now my lead hammer is destroyed, and I will have to recast it, no biggie. So, I move to the ball peen. I put the ball end against the pinion, and with everything I can muster, hit it repeatedly with the single jack. The pinion has not moved a bit. It's been soaking in penetrating oil over night, so maybe something will budge today. The only solution I can think of is a bigger hammer. Any of you all got any idears???

I am thinking of using a butane pencil torch to heat the bearing to maybe get it to expand. I do not own a press, and want to avoid loading 300 pounds of axle housing into my truck to pay someone to press it out....

[This message has been edited by mofugly13 (edited 05-08-2004).]

Jason J
05-08-2004, 05:38 PM
Well, if you have never set up a pinion, you are skating on thin ice. Did you take the measurements BEFORE you tried to remove the pinion? It may well be to late now, since you don't know if it has moved or not. I would strongly suggest that you refer the job to qualified service personel, as they say. You may well end up with nothing but junk, and noisy junk at that. Or you may well have the rear end seize at speed.

That being said, most likely you are fighting some high strength loctite here. (Green or Red) You might as well heat the heck out of the pinion bearing to get it apart since you won't be able to re-use the pinion bearings anyway. It will take 400* F or so to get the Loctite to give up.

05-08-2004, 07:11 PM
Dana's use a crush ring. I'd consult a expert.. or read a alot..

David,, (about ten into a twelvepack here)

05-08-2004, 07:25 PM
I appreciate the concern, but I have read everything I can find on setting up gears and I have excellent mechanical ability, and I'm not stupid. I thoroughly understand what it is that I need to do in regards to setting them up, and of the crucial measurements/preloads I need to be aware of. I am replacing the ring and pinion, as well as all the bearings and seals, so If the bearing is ruined in the process of removing the pinion, oh well. Telling me to take it to the appropriate mechanic is like me telling some of you: "...looks like you better take it to a machine shop." The D60/70 do not use a crush sleeve, they use preload shims. This I know because I have the install kit right in front of me and it has shims, unlike the diffs on my Toyota, which use a crush sleeve.

Is it common to use loctite on a press fit bearing? I can imagine the use of loctite on the pinion nut, but on the bearing????

[This message has been edited by mofugly13 (edited 05-08-2004).]

05-08-2004, 07:36 PM
I thought I would mention that I had an extra rear end, and ask what gears you were heading for in the swap, but with you all the way across the country, the shipping would kill the deal unless I just wanted to pay you to take it.
Good luck with it, David from jax

05-08-2004, 07:49 PM
Thanks, Dave. I already have the gears, tho. 4.11, I'll be running 35" BFG Mud Terrains.

05-08-2004, 08:52 PM
No sweat,all you need is some big all thread rod,nuts,a bottle jack and some scrap iron.

Make yourself up two bars both the same length out of something heavy(1x2"flatbar)long enough to span the open end of the chunk housing plus a little more for the all thread rod.Allthread should be substantial(3/4" at least)you will need two 36" lengths of it and four nuts.Drill a clearence hole in each end of the flatbar to clear the all thread at a center distance wide enough to clear the sides of the chunk housing.Place one flatbar over the opening,set your bottle jack(12ton,20 would be better)ontop of the pinion with a steel plate under the jack base(to keep the pinion from cracking the jack base)place the other flatbar ontop of the jack,install and tighten the allthread rods making sure the centerline of the pinion and jack are lined up,and then jack away.

For safty you might want to wrap the whole mess in a towel,just in case something should shatter.Also you may need to reinforce the bars if they start to bend,if this is the case weld a rib of flatbar standing on edge to the back of each bar and try again.

If that doesn't get it then the only other way I know of is to cut the bearing cages and extract the rollers one at a time until it fals out,this usually requires a torch and much cursing.

05-08-2004, 09:11 PM
Thanks, wierd! I like the idea of building a press of sorts around the housing, and was tossing that idea around when I first got into this predicament. Only prob is that I don't have any flat stock at my disposal... Guess I'll have to buy some or scrounge some up at work.

05-08-2004, 10:11 PM
I like Wierds idea. Might I suggest that when you have it under good load then give it a smack with a hammer.

Or, you could just hoist it up about three feet above an anvil with some poly rope and burn the rope till it lets it drop straight on the anvil.

[This message has been edited by Evan (edited 05-08-2004).]

05-08-2004, 10:21 PM
I am a big fan of the expansion rules. After a tool box i bought a set of torches. However the rules works both ways. Here we can buy this stuff called "Givreur". Basically it is ice in a can. You spray it on shafts you want to shrink a bit in order to slip bearings on.

It will take a lot of this stuff to cool an area but it is an option. Personally, and i like saving a buck or two, but i would get a friend to press it out or at least torche it. The time you will spend driving around getting metal, building a press, etc is valuable driving time wasted.

I wish you luck. Keep us posted

Rob http://bbs.homeshopmachinist.net//smile.gif

05-08-2004, 11:59 PM
I got it!!! I decided to try the heat thing. I went downstairs and pried out the pinion seal, then I got the propane torch out and went around the outside of thebearing with it a bunch of times. I saw the penetrating oil I had sprayed down there start boiling out of the crevice between the bearing and pinion, so I put down the torch, grabbed the ball peen and single jack, and a few good whacks later, it was out. I feel better.

Mike W
05-09-2004, 04:30 AM
I like to hear a success story.

05-09-2004, 04:59 AM
35's on a D70? How much clearance will you have under the diff, especially after you air down? 4:10's will be nice on the freeway though. My Tacoma hunts between OD and 3rd on steep hills with 32's,4:10's, and Auto trans.

05-09-2004, 05:26 AM
The pumpkin on the D70 sticks down only 1/2" or so farther than a D60, so clearance is cool, and I wont be airing down much,as this is my daily driver, logging trail rig. I wont be doing rocks with the K5.....just yet. Most Chevy truck owners who swap in 1-ton axles swap in a 14-bolt, that pumpkin is huge and ground clearance becomes an issue. But then again, most who go 1-ton go with 38" tires or bigger. I looked for a D70, 'cause I wanted to be different. The 14-bolt has all sorts of reinforcing ribs cast into the bottom of the housing, that combined with the low hanging pumpkin makes for the possibility of hanging up the diff. The D70U is very smooth along the bottom of the pumpkin.

With 4.10 and 35" tires, I'll be running higher RPM's at 70mph than with the 3.08 and 33"s I am running now.

[This message has been edited by mofugly13 (edited 05-09-2004).]

05-09-2004, 06:13 AM
Sounds like a nice rig. What motor and trans do you have? You are near Pirate (POR) country, do you go to their forum? I do but I just lurk as I drive a Tacoma (AKA Camry), and I'm just a noob LOL. Lots of good info there.

05-09-2004, 07:49 AM
I have a Goodwrench crate 350, and a th350 I had rebuilt about a year ago. I do go to POR, same screen name as here. I go there mostly for the tech archive, I think I've only posted once. With the axle swap/gear change I've read up on everything I can find there, which happens to be a whole lot, as you probably know. I mostly (well actually 99% of the time I'm connected) go to www.ColoradoK5.com, (http://www.ColoradoK5.com,) as it is an extremely helpful site that is specific to chevy trucks. My K5 is my DD as well as the ride that gets me to my hunting cabin on a few miles of dirt road. Once there I have a Suzuki Samurai that I use to get around. I have an '82 Toyota 4wd sitting in my driveway with a blown engine, (blown up, not supercharged) I would really like to make that a dedicated trail/rock wheeler. My grandpa bought it new in '82, and it's made its way from him to my dad to me. Of the three 4x4's that I own, I'd have to say I am still most impressed with how the Toy handled off-road. It's got a 3" lift and 31" tires, otherwise totally stock, and I have taken that mofo into some really hairy crap and it always got me out in one piece. I'd really like to get it back on the road/trail, but that will happen as finances dictate. Nice to see another wheeler on this site.

[This message has been edited by mofugly13 (edited 05-09-2004).]

jim davies
05-09-2004, 07:03 PM
One thing that can happen with rear Danas used offroad is that the bottom of the tin cover gets pulled back by a rock and all the lube leaks out. Check and see if the cover is larger than the casting at the bottom and/or replace it with one from a front axle [about twice as thick.]

05-10-2004, 10:41 PM
The D70 uses the same diff cover as a D60, even though the housing is larger. This leaves about 1/4"-3/8" of housing "lip" protruding below the bottom edge of the cover, so I'm good to go.

05-10-2004, 11:47 PM
I am not a 4x4 nut, but we have one in the neighborhood. He got wind of my "JUNK" and came to look. He just had to have one of my winches,(Ramsey 12K, chomed from the factory) so I got my house repiped (He is a plumber).Then I had to build the bumper for it to sit in. Now he is looking at the floating transfer case I have stashed, and I want the garage piped, upstairs and down. Both of us are stalling, hoping to get the other one to sweeten the deal before the other agrees to it.
We have a mudhole in the property across the street. They like to play in it. If you go down into the woods a little further, you can find a D-9 dozer, buried up to the top of the seat, been there for at least 30 years. Too much mud, too far back in the woods, too old to salvage.
David from jax