Technical Rear axle question

A friend of mine called me this morning and was on his way home from purchasing a 1965 Dodge truck, He went on to say it had a small dodge V8 - I believe he said 318 column mount 3 speed and so far the truck was running great, but he said on deceleration the rear axle whined but not on acceleration.

He told me the owner said the rear axle was from a late model ram truck.

My first thought was to take it to a station with a lift and check the rear axle and see if it was low on fluid, if not the rear axle will need attention sooner or later and being 300 miles from home I suggested to keep driving.

What do you guys think? HRP

 

I've had pinion bearings cause that, ran a long time that way. But, of course, YMMV. Literally.

 

My late model daily driver Dodge Dakota has a whiney rearend, probably since new. It now has over 225,000 miles.

 

Louder exhaust

 

A whine on deceleration only sounds like gear noise. If that's what it is, it will run forever. I would check to see that the pinion nut was tight though.

 

I watched a youtube video on this .... I'm a expert!

A guy was installing a new upgraded ring & pinion that he bought from sumitt.
He had the same problem, noise on deceleration ... He really thought it was too much play when he set up/shimmed the ring & pinion. .... Long story short sumitt sent him a new set and was the way the gears were cut a defective part.

Thats not the problem with a 1965 Dodge rear end, most likely is just too much play in the ring & pinion. While it is up in the air for inspection, check for how much slop is in the rear end by turning the drive line by hand and how much play in it before it engages the ring gear. That will tell the story.

On a good note, pull the brake drums, unbolt the axles, u-joint, center section and pull it out.
Bolt in a new or used one, ...... First time I changed the rear end on my 1961 Dodge truck I think it took about 1 hour.

 

A friend of mine was a dealer mechanic. A rear axle whine, sometimes a T-case for 4x4s, was fun to diagnose. Check tolerances, replace bearings, even checking the axle for misaligned axle tubes. Sometimes the entire axle housing would be replaced. Set it all back up.
About 10-20k miles later some would come back. Some traded off.
it seems some are just gonna be louder than others and live forever that way.
I’ve seen some odd drive shaft harmonics sound like a rear axle noise.
If the pinion is good, let er eat.
my flatbed has all kinds of old truck noises. I guess I just expect it.

 

Most all later model 93 up Dodge/Ram trucks had rearend noise. I think at one time the Gov't was looking into them.

 

Did he check the grease?

 

I knew I had a reason to avoid Mopars, but the government is trying to stay away from them too?

 

Used to be on the troubleshooting section of manuals, they would have a “how to diagnose “ thing for rearends, like noise on steady cruise, accelerating, coast, etc.

 

Rear end noises on dodge pick ups are some what normal. But with that being said, it does need to be diagnosed to be for certain.
When I worked for Dodge, I saw the same noises so many times that I could park a truck near a wall, rev the throttle and tell you whether it needs a water pump, a clutch fan, a catalytic converter or all of the above.

 

I've heard sawdust will quiet one down. Never tried it, just heard that from a friend....

 

Never used sawdust , but I had a old Chevy I packed full of chassis grease and drove it for a long time when I was young.

 

I have done it at work a few times on forklifts with noisy diffs or drive units if it was the crown and pinion making noise .

slather is up with valve lapping compound and spin it by hand a bunch of times . Then clean it out very very well .
noise gone.


Also got lucky a few times with pinion noise , loosen the pinion nut and tighten it back down .

not “ proper” repairs , but worked and lasted a very very long time.

as has been said if the rear end is not falling apart ( gears , bearings , no leaks etc) in good shape you should be fine .

 

Bananas will quiet it down. But boy does it stink when you finally change it out.

 

One of the first things I would do is put an 8-3/4" back in it. They're a lot easier to work on and parts are more plentiful and less expensive.

 

I talked to Jim and he had just got home without incident, he said he stopped at a small station and they put the truck on the rack and checked the rear and it was fine, Jim said he finally got use to the noise after driving 583 miles. HRP

 

Hammer down.
2 possibilities.
1: it takes a complete and total dump and possibly spits out a part or two.
2: nothing.

I don’t sky dive but I do drive an old truck.

 

My old truck has about 160 thousand miles on the odometer and the rear axle has been roaring on deceleration for more than 100 thousand of those miles, the noise is annoying and at thois point in time really not worth the trouble of trying to repair it.

 

First he had it checked to be sure something wasn't really wrong with it, then he just drove it. After 583 miles, he got used to the noise.

Sounds like the process of getting to know almost every old car or truck to me. Once you get used to the noises omitted, you drive them. Then, if the noise changes, something is probably wrong! Its when that expected noise disappears completely that is the most scary...