broken pin bolt

85 S-10 Blazer 2.8 4X4 . Rear end gearing 3.73 with locking differential. I bought this old Blazer for my son and I to have a progect but looks like it may be a bigger project then expected . The axle seals were leaking , I told myself no big deal just have to pull the axles and replace the seals. But when I got in the Diff. The pin bolt was broke off. is there a way to get that out or will I just have to junk the rear and go get one from a bone yard hoping that it'll be allright??? I'm really hoping that there's somebody out there that knows how to get this out ! I allready have to buy a gas tank and sender for the dumb thing. Thanks for looking and for any comments that could point me in the right direction. Thanks Dave

Yes, there are ways to remove the broken pin. The easiest and fastest way involves the use of a mig welder. Have a spray bottle of water readily available. Mig weld a "booger" on the end of the pin large enough to grab with vise grips. Immediately after welding, spray it with water. The heat from welding expands the pin and the water contracts it rapidly which helps break it loose. Turn it out with the vise grips. Another way is with a pin point punch and a hammer. "Walk" the pin out being careful not to damage the housing. The use of an "easy out" is not recommended due to the shavings involved when drilling. The threaded part of the pin is approximately 1/2" long and the pin itself is approximately 1 1/2" long. Good luck, hope this helps.

the pin bolt bfoke off just at the start of the threads , it is broke off about 1/2 to 3/4 of an in. inside the housing. thanks for the 1 reply . Dave

Ouch! If I understand your description, it sounds as if most of the threaded part of the bolt is out, yet the straight part of the pin is still locked into the spider gear pinion shaft, correct?

If that's the case, your only option may be to drill through the pin and plan on replacing the pinion shaft as well. If the bolt was sheared from the pinion shaft spinning, you won't be able to re-use it due to the damage. You will need a carbide drill to get through the bolt and shaft. A strong magnet placed near the opening should catch most of the chips, but you should plan on cleaning and flushing everything with solvent to make sure any chips stay out of bearings.

Good luck with that one. It's not a fun job, especially if there is little room to work under the vehicle.

are you referring to the big pin that the pin bolt slides into that is about an In. across? If so drill this till you completly drill to the same diameter of the pinion shaft? And with the pinion shaft spinning could it have damaged the pinion itself?

And if it's broke on the other side of the pinion shaft will I be able to remove the remander of the pin from the pinion with no diffaculty?

I understood this is the bolt that broke, being that it's fairly common for these to break: http://i100.photobucket.com/albums/m23/curly_bone85/mainpinbolt.jpg correct me if I misunderstood.

Sometimes you can take a small magnet small enough to go in the hole and work it out.
Spray in here with carb cleaner and hand wiggle the spider gear pin around.
Also if you can figure out where the end of the broken pin is you can drill a small hole around a 1/16 inch right behind the end of it and blow it out with air pressure or tap hole for a grease zerk fitting and pump it out with grease gun.

Or as said start drilling with a hard drill bit.
Blue point/snap on makes a no. 1 drive in easy out that that will bing it out if you can can get a 1/8 bit to drill a little ways into the pin.
The broken part of the pin is usually not tight in hole but a bear to get a hold of to pull out.
Last resort you can hammer the spider gear pin out but it usually cracks the case when you do that.
Good Luck
MT

You are correct on the photo

As mentioned earlier, not a fun job, the entire pin must be removed. A well stocked auto parts store will have a replacement pin, if not, time to visit the dealer.

I went out and bought a 1/2 in drill bit today to finish drilling the pin out . It cost me 40.00 . But it looks as though the pin is going to be drilled even bigger then that boy I did'nt realize that a drill bit that size and would drill the hardend metal cost so much I hope I dont have to go out and buy one yet bigger then that . If I do I could have bought a whole rear and just swapped it.I will let you'll no how it turns out , thanks for all the advice.Dave

Careful now, the pin is only about 5/16" diameter! Better get a new pin first and measure it before you start drilling away with that 1/2" jobbie.

I got the pin and the rest of the pin bolt out and replaced the axle seals and got it all bottoned up today. I took an old rear end apart that was out on the farm and the pin bolt and pin were in great shape ,so I used them. it was a bitch getting it all drilled out , but did'nt give up!! I thank you for your advice! job well done!

I've had this broken pin problem before. I used a kit I bought. Can't remember who made it, but it was called a differential pinion bolt extractor. I think I got it on ebay a few years ago. Couldn't believe it worked in 10 minutes and with no damage to the carrier.
Hopes this helps someone with the same problem.

Lenny