Axel shaft hot

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V8 Sam

V8 Sam

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Afternoon peeps!

Just came back from a little trip in the dart and noticed that passenger side rear axel shaft was ROASTING hot.

The drum was cool so ruled out a brake binding issue

Driver side was cool as a cucumber, passenger side super hot. Couldn't even touch it.

Only thing I've done recently is new lug nuts but can't see that causing it.

Wanna have some sort of idea where to start before I look into it.

What we think? Bearings maybe?

They are the timkin tapered type.

70 dart
8.75 suregrip axel, 489 case 3.55 gearing. Standard length a body SBP halfshafts (all tho housing was narrowed from a b body)

Thanks!

Sam.
 
Bearing preload set correctly? Or you may have a bearing going out, but I would expect some heat transfer through the drum.
 
Seems like a bearing to me if your brakes are cool.
Check your end play in that axle once on jack stands, there should be a little play when pulling & pushing the axle,(you will have to check abodiesonly for tolerances). I think its .006”-.010” but don't quote me. If no issues pull the axle and inspect for heat colour,wear and smell for nasty toast.
Gear oil level ok? Should be since its only one side you say but never hurts to check.
Another thing to check would be that whoever welded the B body housing to an A maybe didn’t get the flange true/ straight. I have seen poorly welded flanges before and usually the axle is very difficult to remove and is holding the bearing wonky causing uneven load on the bearing.
If you have had the rear end in the car for a long time then the latter might not be the case.
 
Time to disassemble and have a look. Since we cannot see it and you can, that's how this is done.
 
Thanks for replies

How will I go about finding what tolerance it's at as I don't have a gauge to measure it with, is there a tried and tested methods otherwise? There should be only very slight movement in and out with the shaft in place? None at all it needs backing off, load and loads it needs adjusting up correct?

Gear oil level should be spot on was only filled recently, will double check.


Gonna jack the back up tomorrow see how freely it spins etc. And try taking the shaft out. Not had a chance yet.

As for the axel narrowing that was done by someone who knew their onions and the axel went into the car pretty easy nothing seemed out of place or untrue, all though it has only been in the car a little while, last few runs have been more.of a shake down seeing how it's all running now it's back together.

The shafts and bearings are of unknown age though as u got a good deal on them as I wanted to keep my bolt pattern so bearing is still the most likely culprit I think.

Anything in particular I should look out for when the shaft is out? Hoping might just need some extra grease packing in it for an easy fix! If only!
 
The simple, truthful answer to your last post is.........You need to read THE BOOK

Go over to MyMopar and download a service manual. Free.

Some Mopar axles use tapered bearings which must be adjusted for preload on one side, which pushes clear across and loads the opposite bearing on the other side as well

If the bearings have been converted (by a previous owner?) to ball type bearings, the preload system will no longer be used.

But some axles use straight needle rollers which run directly on the axle, and are retained by "C" clips in the differential. If that is the case with you, it might be as simple as low fluid level, and has torn up a bearing.
 
Axle might but bend a little bit and stressing out the bearing. Or bearing is going out
 
l love that you know someone who knows their onions!
Kudos to them.
Maybe there is a video on how to check endplay without measuring devices.
Good luck tomorrow and keep is posted!
 
QUINN FORBES said:
l love that you know someone who knows their onions!
Kudos to them.
Maybe there is a video on how to check endplay without measuring devices.
Good luck tomorrow and keep is posted!
Click to expand...
Yeah comes in handy haha! he's very well known UK wide.

I'm still gonna think this is worn bearing related, as I'm not sure on the history of them. will have a proper look tomorrow, just wanted to go armed up with as much info as to what to look for as possible

Tempted to just wack green bearings in and then I know it's not that.
 
Member Cannucky had a shortened to A rearend.
His passenger wheel had 1/4 inch toe-in.
Don't remember why we checked, - possibly heat, certainly not wear on those 12?" wide drag radials, lol .
Perhaps check your rear toe ?
 
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Not sure about green bearing but i’ve heard good things.

So I downloaded the previous mentioned free service manual and its sweet!
I know you said you don't have a dial indicator but this is the procedure and tolerance’s copied straight from the manual.
For when you reassemble.


Checking for Runout and Zero End Play

AXLE SHAFT END PLAY

CAUTION: When setting axle shaft end play, both rear wheels must be off the ground, other- wise a false end play setting will occur.

(1) Using a dial indicator mounted on the left brake support (Fig. 14), TURN THE ADJUSTER CLOCKWISE UNTIL BOTH WHEEL BEARINGS ARE SEATED AND THERE IS ZERO END PLAY IN THE AXLE SHAFTS. BACK OFF THE ADJUSTER COUN- TERCLOCKWISE APPROXIMATELY FOUR NOTCHES TO ESTABLISH AN AXLE SHAFT END PLAY OF .008-.018 INCH.

(2) Tap end of left axle shaft lightly with a non- metallic mallet to seat right wheel bearing cup against adjuster, and rotate axle shaft several revolutions so that a true end play reading is indicated.

(3) Remove one retainer plate nut, install adjuster lock. If tab on lock does not mate with notch in adjuster, turn adjuster slightly until it does. In- stall nut and tighten 30-35 foot-pounds.

(4) Recheck axle shaft end play. If it is not within the tolerance of .008-.018 inch, then repeat adjustment procedure.

(5) Remove dial indicator and install
 
Yep would say your axle preload on the passenger side is too tight.

Feel the center chunk if that gets hot, not just warm.

Jack it up and roll it over by hand in neutral to see what you can feel on the passenger bearing. If it's hard to turn, that's your first clue.
 
George Jets said:
Yep would say your axle preload on the passenger side is too tight.

Feel the center chunk if that gets hot, not just warm.

Jack it up and roll it over by hand in neutral to see what you can feel on the passenger bearing. If it's hard to turn, that's your first clue.
Click to expand...
On an 8 3/4" axle there's adjustment only on one side since the axles are able to slide back and forth and press on each other by the thrust button inside the differential. You'll have a hard time getting it right without a dial indicator, very difficult to tell the difference between .010" and .030" of play just by feel unless you have a lot of experience. Many times I thought it felt right and then I put my dial indicator on and it was way off.

It's a good tool with a lot of uses, you don't need a fancy expensive high-precision one either. I imagine in the UK you can find a dial indicator with magnetic stand kit for a reasonable price. May be tougher to find one in inches as opposed to metric but still, it's a fairly common tool.

This is the one I have: Summit Racing SUM-900016-1 Summit Racing™ Magnetic Base and Dial Indicator Kits | Summit Racing
 
MopaR&D said:
On an 8 3/4" axle there's adjustment only on one side since the axles are able to slide back and forth and press on each other by the thrust button inside the differential. You'll have a hard time getting it right without a dial indicator, very difficult to tell the difference between .010" and .030" of play just by feel unless you have a lot of experience. Many times I thought it felt right and then I put my dial indicator on and it was way off.

It's a good tool with a lot of uses, you don't need a fancy expensive high-precision one either. I imagine in the UK you can find a dial indicator with magnetic stand kit for a reasonable price. May be tougher to find one in inches as opposed to metric but still, it's a fairly common tool.

This is the one I have: Summit Racing SUM-900016-1 Summit Racing™ Magnetic Base and Dial Indicator Kits | Summit Racing
Click to expand...

Setting End Play, 8 3/4:

Screenshot_20230209-143206_Firefox.jpg
 
inertia said:
You wouldn't have an exhaust pipe aimed at the axle ?
Click to expand...
Good question! That is such an obvious thing I never would have thought of suggesting to check the exhaust.

As have most others here have already mentioned, I immediately expect it to be a bad bearing. My only thought about that, is it takes very little roughness in a bearing to produce heat and noise under load. Thus it probably makes sense to change the bearing even though it may feel just fine in your hand.
 
MinnesotaMopar said:
Good question! That is such an obvious thing I never would have thought of suggesting to check the exhaust.

As have most others here have already mentioned, I immediately expect it to be a bad bearing. My only thought about that, is it takes very little roughness in a bearing to produce heat and noise under load. Thus it probably makes sense to change the bearing even though it may feel just fine in your hand.
Click to expand...
Get a stethoscope, you'll hear a bad bearing using the needle, lotsa other uses as well .
 
George Jets said:
Setting End Play, 8 3/4:

View attachment 1716047049
Click to expand...

Not sure what you're trying to show? You can measure end play on either side axle as long as the opposite side is seated fully outward against its bearing race but it makes things easier if you do it on the side with the adjuster. Again, if both sides could be adjusted independently there wouldn't be a threaded adjuster on only one side axle tube end. You're adjusting total end play for both axle shaft bearings which is why you have to tap one end in to take up any slack between the inner ends of the axle shafts and thrust button as well as the bearing. Post #14 describes the process straight from the FSM.
 
Funny...I was always taught to tighten down the adjuster until no play. Back it off a tad and then just push-pull on one axle back and forth pretty hard. If you could hear it "thunk" back and forth but not feel it, you were good to go! More evidence of me being just a hack!!

Seriously, you'll get a feel for what's in range pretty quickly if you do this and then measure it.
 
Demonx2 said:
Funny...I was always taught to tighten down the adjuster until no play. Back it off a tad and then just push-pull on one axle back and forth pretty hard. If you could hear it "thunk" back and forth but not feel it, you were good to go! More evidence of me being just a hack!!

Seriously, you'll get a feel for what's in range pretty quickly if you do this and then measure it.
Click to expand...

I think having it "too" loose is OK to a degree, it's when you have them too tight that bad things happen.

I'm just a stickler for following instructions lol especially from the FSM. Rather not get into a habit of thinking I know better than the people who engineered the cars in the first place.
 
Thanks for all the replies peeps! Got plenty to checkout

Haven't had a chance to check yet! It's been horrible and cold over here! And the car isn't coming out the garage anytime soon

Soon as I discover whats what I'll let you know
 
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