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diff plug

D

dirtynails

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So I wanted to replace the gear oil in the rear diff today, and replace the old gasket with a new one so it wouldn't leak. I got the cover off. I painted the cover. It looks real nice. When I went to remove the fill plug so I could fill it, I discovered it was rounded pretty good. I never did get the damn thing off after trying different things. My question is can I drive it empty my favorite transmission place to get it off and replaced. It's only one and a half miles. Seems iffy to me what do you think? Do I need to have it towed instead?
 
I've had those stupid stock plugs with the square drive "hole" strip out too,one I had to drill & use a E-Z out on it to get it out.asnd I replaced it with a plumbing type with an external square head on it instead,it was 3/8" NPT..I think some moron used an impact gun to tighten it somewhere along its life before I owned it!..I thought I'd snap off the E-Z out as I was removing it,it was torqued really good!.:mad:.luckily it did not..on another stuck plug I ground down a hex bolt square ,and pounded it into the plugs square hole with a hammer,and gave it two quick spot welds with my arc welder and used a pipe wrench on the bolt to twist it out..

I have since used brass hex head ones on my plow trucks so the corrosion wont be a problem again and teflon pipe dope helps a lot to prevent them from getting seized up too..they dont need to be really "tight" either,a good snugging is all you need..they also sell magnetic ones,but I'd prefer a magnet epoxied to the bottom of the case,so a string of chips and filings wont be dangling near the gears & bearings,to better protect them..I remove those stupid GM ones as soon as I get a truck now,and most of them were already "boogered" by the time I got to them!..
 
I wouldn't want to drive my rig a mile and a half without any gear oil, but that's me. You could probably do it if you drove real slow. You could pick a up a diff cover at a bone yard cheaper than paying a transmission shop to take the plug out for you. I would go that route myself, if I couldn't get the plug out.
 
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Aha, that explains the other post.
Basically, don't do it. For the price of one bearing, you could take the cover back off, walk to the shop, get it replaced and hitch a ride back with someone at the shop going to lunch and be money ahead.

And if you damage anything else, its going to be expensive.

If its a square head plug, vise grips or a small pipe wrench should get it off.
If its a socket head, pull the cover back off, drill a hole in through the plug, clean off the chips, put the cover back on.
Fill it through the drillhole, drive a plug of some kind in the hole. Wooden plug will work, and then drive it to the transmission place.

If you tow it of course, the rear wheels have to be off the ground.

J.
 
He's talking about the rear differential. Typically, the rear diff cover doesn't have a fill plug on the cover, it has the stupid fill plug on the side of the housing.


If that's the case, you should be able to hammer an old 3/8 extension in there and work it out. The hammering will also loosen any rust or corrosion that might be keeping it from coming loose easily. I had the same problem with my Sub when I got it and changed the fluid last summer. A new plug isn't any more than a couple of dollars at the parts house.
 
snuffy74 said:
He's talking about the rear differential. Typically, the rear diff cover doesn't have a fill plug on the cover, it has the stupid fill plug on the side of the housing.


If that's the case, you should be able to hammer an old 3/8 extension in there and work it out. The hammering will also loosen any rust or corrosion that might be keeping it from coming loose easily. I had the same problem with my Sub when I got it and changed the fluid last summer. A new plug isn't any more than a couple of dollars at the parts house.
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OK, I knew a Ford 9inch had it on the side of the housing, but I thought most GMs had one in the cover.
 
Take the cover back off, fill a gallon ziplock bag half way with gear oil and stick it in the diff. Put the cover back on and go. The plastic bag will get chewed up and won't hurt anything and you've got oil in your diff. Wahla
 
gone huntin said:
Take the cover back off, fill a gallon ziplock bag half way with gear oil and stick it in the diff. Put the cover back on and go. The plastic bag will get chewed up and won't hurt anything and you've got oil in your diff. Wahla
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I have done that after i broke an axleshaft in my 12 bolt. it works great. however i dont think its a good idea in the long run, as i have overhauled diffs because people didnt clean the silicone out of the diff when doing a service. when the silicone gets stuck in between the rollers, it wipes the gear oil away for the next roller inline, starving it of oil.
having said that, i drove mine for 2 years after i put that plastic bag in mine, and the axle still workied fine.
 
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