Differential and other maintenance

[K10-Kansas]

I brought my truck home several weeks ago and was wondering, should I change the differential fluid and diff gaskets just incase it hasn't been done in decades?

The truck has a brand new engine, transmission, radiator, break booster and master cylinder so I know those fluids are good, but what things should I do
maintenance on now or soon that possibly could have been neglected for years?

[yuccales]

Absolutely won't hurt to do both those diffs, transfer case. Bust out that grease gun and lube the heck out of that truck. Peace of mind is worth the cost in parts.

[Getter-Done]

Yes .
The Rear axle fluid change is a great idea for peace of mind.

I would pack the front wheel bearings also.

[Stocker]

My personal favorite for sealing differential covers is Permatex #81182, made to use with gear oil.
I like to use a gasket and put a thin coat of Permatex on each side of it.

[K10-Kansas]

Originally Posted by Stocker

My personal favorite for sealing differential covers is Permatex #81182, made to use with gear oil.
I like to use a gasket and put a thin coat of Permatex on each side of it.

Great, thanks. I saw a guy use a liquid sealer because he didn't have a gasket. Seems like a great idea to do a thin bead in addition to a gasket.

[K10-Kansas]

Originally Posted by Getter-Done

Yes .
The Rear axle fluid change is a great idea for peace of mind.

I would pack the front wheel bearings also.

I went and got some wheel bearing grease yesterday. I have to change some studs anyway on the drivers side front. Should I also replace the bearings or only if they look bad?

[Accelo]

If the bearings look good it's OK to reuse them.
Front wheel bearing almost cost less than the chemicals used to clean used ones.
They will be China built bearings for course. Others cost slightly more if you can find them.

The newer GM trucks do not come with a rear cover gasket. GM used the silicone sealer only.
Cheers

[Chevy nutcase]

Differential oil is probably the most forgotten region of any vehicle. If it's still moving it's fine is an unspoken motto of car and truck owners. Its possible you'll be draining the factory gear oil. Your truck will thank you

[K10-Kansas]

Originally Posted by Accelo

If the bearings look good it's OK to reuse them.
Front wheel bearing almost cost less than the chemicals used to clean used ones.
They will be China built bearings for course. Others cost slightly more if you can find them.

The newer GM trucks do not come with a rear cover gasket. GM used the silicone sealer only.
Cheers

O'Reilly had some $12 bearings and some $22 bearings. He was adamant that the $22 were higher quality. I guess I'll hold off and see what the bearings look like. Thanks.

[Getter-Done]

Originally Posted by K10-Kansas

I went and got some wheel bearing grease yesterday. I have to change some studs anyway on the drivers side front. Should I also replace the bearings or only if they look bad?

Only if they look bad.
The ones you have may be better than some of the one on the shelf nowadays.

[Accelo]

"I guess I'll hold off and see what the bearings look like."

I made my living in and around bearings. You will not be able to see any difference. The difference will be in the steel composition and heat treating and the size. However, the size difference will be in microns, and the average guy will not be able to measure this tolerance. The same with the heat treating.
I will say this, even though I don't like to. In the front wheel application the bearings are not heavily loaded. The length of time, the bearings last, will likely be related to how clean you get the parts, what type of grease you use and how they are adjusted, not the manufacture.

This is not always the case. But their, I said it and don't feel any better.
Cheers

[Steeveedee]

I'd look for bits of metal in the bearings. It'll be obvious, if they are bad. I will change them regardless, if the cup has a sharp edge at the inside of the hub. If you use the old bearings and dry them with compressed air, please resist the urge to spin them up to jet turbine speeds. It ain't good for them. My ex-BiL used to do that, and I always waited for one to grenade in his hand.

[K10-Kansas]

Originally Posted by Steeveedee

I'd look for bits of metal in the bearings. It'll be obvious, if they are bad. I will change them regardless, if the cup has a sharp edge at the inside of the hub. If you use the old bearings and dry them with compressed air, please resist the urge to spin them up to jet turbine speeds. It ain't good for them. My ex-BiL used to do that, and I always waited for one to grenade in his hand.

Every plastic part on the truck I touch just cracks and several of the bolts break when removing them. I feel like everything I touch I should just replace with new. So you put in new bearings as a rule of thumb?

[K10-Kansas]

Originally Posted by Accelo

"I guess I'll hold off and see what the bearings look like."

I made my living in and around bearings. You will not be able to see any difference. The difference will be in the steel composition and heat treating and the size. However, the size difference will be in microns, and the average guy will not be able to measure this tolerance. The same with the heat treating.
I will say this, even though I don't like to. In the front wheel application the bearings are not heavily loaded. The length of time, the bearings last, will likely be related to how clean you get the parts, what type of grease you use and how they are adjusted, not the manufacture.

This is not always the case. But their, I said it and don't feel any better.
Cheers

I do a really clean, slow and careful job and I bought some good bearing grease. So those things are covered. The "how they are adjusted" part might be a trick though since I'm a novice mechanic.

[Steeveedee]

Originally Posted by K10-Kansas

Every plastic part on the truck I touch just cracks and several of the bolts break when removing them. I feel like everything I touch I should just replace with new. So you put in new bearings as a rule of thumb?

No, I inspect first. I'm a real skin flint, and don't want to taste my money or that of a customer. I've installed literally hundreds of bearings, having worked as a mechanic for many years. You can download the service manual for your truck from the posted link (it's a '77 underneath, right?). It'll give you guidance on just about anything you want to tackle.

http://67-72chevytrucks.com/vboard/s...d.php?t=545416