Grinding noise from front drivetrain

Tiny
GWATTS1040
  • MEMBER
  • 1984 JEEP CJ7
  • 150,000 MILES
1984 jeep cj7, I ran the front hubs in 4x4 for a few days and cycled through 4 hi and 4 lo. After doing this when I selected 4x2 and started to drive a loud grinding sound came from the front drive. Once I reselcted 4x4 on hubs no more grinding. I repeated this and the noise returned if not immediately very shortly after, with 10 minutes. I was doing this because it felt like less drag in 4x4 than 4x2 and the hubs were replaced a year or so ago and I was trying to determine if the could possibly be in backwards. Some turns were made on hard servace in 4 wd.
Sunday, June 26th, 2011 AT 11:02 PM

13 Replies

Tiny
RASMATAZ
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You sure its not coming from the transfer case-How's the fluid level in it-
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Sunday, June 26th, 2011 AT 11:29 PM
Tiny
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With your Transfer case in 2WD HIGH, hubs disengaged (4X2, if written on your hubs)

At each knuckle--drivers and passengers, see if you can freely spin the "U" Joint in the center of the knuckle, with the wheels on the ground.

Any resistance or hard spots or it won't move?

Keep me informed

I can help you, CJs are sorta my AO (Area of Operations)

We will continue, till you are tired of me!

Never had any other vehicle since I've been driving, presently on #6 and #7

Raz, I'm in Hawg Heaven Now. One finally broke, after months of waiting!

Check on me, but I think some Computer car might need YOU worse!

The Medic
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Monday, June 27th, 2011 AT 1:35 AM
Tiny
GWATTS1040
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Follow up. Tested the u joints they are easily turned on both sides. The grinding and growling is still there and you can feel it in the steering. However when you back up it neither growls or shakes.
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Tuesday, June 28th, 2011 AT 12:08 PM
Tiny
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Gwatts1040

Its been too long buddy!

I have given you plenty of time to return with info

I know exactly how you feel

Broke Jeep--End of the World.

It's not, we can make it better!

Suicide is not the answer here. Please don't jump!

Return. We'll get him thru this. He's made it 27 years already, he will live on, if you're there for him!

. But seriously, whats the situation now?

The Medic
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Tuesday, June 28th, 2011 AT 1:34 PM
Tiny
GWATTS1040
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Checked u joints last night, both turn easily by hand with no binding. Growling and grinding heard and can be felt strongly through steering. When driven in reverse symtoms do away. Any other ideas?
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Tuesday, June 28th, 2011 AT 8:03 PM
Tiny
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Is this a Trac-Lock limited slip system (positive traction)? Front or rear or both?

No mention of this in your info. Is this a manual or automatic?

What ever. What tranny and transfer-case do you have?

Sounds as though your hubs do unlock!

Your Turn. Sorry, I've been out all day!

The Medic
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Wednesday, June 29th, 2011 AT 1:32 AM
Tiny
CJ MEDEVAC
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ONCE WE WERE CRAWLING AROUND AT FT. BARTLOW (SAVANNAH, GA.) AT THE TIME, AN "UN-EXCAVATED" CIVIL WAR SHORE BATTERY--SORTA ABANDONED---WE ONLY FOUND IT THROUGH OUR SUPER AIRBORNE RANGER NAVIGATIONAL SKILLS!

SEEMS THAT FT. PULASKI (THE SHOW-CASE NATIONAL MONUMENT, HEADED TOWARD THE BEACH) HAD ANCIENT MAPS OF THE AREA DISPLAYED---AND THEY SHOWED THE BATTERY ON THEM--BUT IT WAS GROWN OVER AND BURIED IN SAND---KINDA LIKE A LOST CIVILIZATION!

WE CRAWLED OVER THE "MOATS AND BARRICADES" A LOT (MEANT FOR NON JEEP PEOPLE!)AND PLAYED IN THE BATTERY FROM TIME TO TIME. USUALLY FEMALES WERE INVOLVED!

THERE WAS A DEEP DEPRESSION IN THE MIDDLE OF THE FORT (OVERGROWN AND JUST LOOKED FUNNY. SAVANNAH IS FLAT!), WE CALLED IT, "THE DEVILS BOWL"

MY BUDDY HAD A CJ7 AND HAD MORE RISK IN HIM, THAN I, SO HE WENT IN IT 1ST

WHEN HE CLIMBED OUT, I WENT (CJ5). WHEN I TRIED TO CLIMB OUT, I GOT A TERRIBLE GRINDING NOISE.I FINALLY HAD TO BACK OUT, TO GET OUT

ON THE WAY TO THE BARRACKS, MAYBE 10 MILES AWAY, I EXPERIENCED A LOT OF VIBRATION. NO GRINDING

WHEN I INVESTIGATED IT THE NEXT MORNING, I FOUND MY BOLTS THAT ANCHORED THE TRANNY TO THE SKID PLATE WERE GONE!

THE REAR OF ENGINE/ TRANNY/ AND TRANSFER CASE WERE SLIDING LEFT AND RIGHT ON THE SKID PLATE----THE GRINDING WAS MY FRONT DRIVE SHAFT (WHEN IN 4x4) HITTING SOMETHING ON THE FRAME (WHILE IT WAS TURNING) WHILE IT WAS SLID TOWARD THE PASSENGER SIDE!

WHAT A SENSELESS STORY (YOU SAY!)----ANY POSSIBILITY OF SOMETHING SIMILAR TO THIS?

THE MEDIC
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Wednesday, June 29th, 2011 AT 1:37 AM
Tiny
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Tranny in neutralEmergency Brake on

Let's grab the yoke against the differential, pull/ shake/ twist/ act like it's a Big-Ole-Spoon, with both hands, aggressively, attempt to stir the insides of the differential

Is there any give. Or is it Rock Steady?

Both hubs unlocked, turn the front driveshaft by hand

Observations?

How about locking in the left hub (Right unlocked), turn the front drive shaft by hand. Both directions

Observations?

Now, lock in the right (unlock the left). Same procedure

Observations?

Now, Lock both in hubs in---By hand, then with a?18 inch? Pipe wrench, attempt to turn the driveshaft

Observations?

Just for giggles!.2WD. Emergency brake on

Lets pull the "Nut Covers", off of the ends of rear axles (both sides).

With a helper, observing one side at a time, sorta try to take off, aggressively dumping the clutch (not too aggressive) Do the nuts spin faster than the wheels?

If so you have stripped a REAR AXLE. It common, it's poor design, if it's original, it's a 2 piece axle. This may account for grinding, and better operation in 4X4. Just being in 4X4, your steering is affected anyway.1 piece set-ups are available, a bit more expensive, for the set. But in the long run, it's cheaper than replacing 'em twice

After some NEGATIVE results.

Next step is gonna be pull the cover on you front differential, and inspect the ring gear and the pinion gear

OK, break it to me

The Medic
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Wednesday, June 29th, 2011 AT 3:30 AM
Tiny
CJ MEDEVAC
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Assuming you checked the Drivshaft "U" Joints too?

The Medic
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Wednesday, June 29th, 2011 AT 3:51 AM
Tiny
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Going back over your question

. While still waiting for you!

I am assuming your question about the hubs and backwards? Meant having them on the wrong sides. NO WORRY. Manual locking hubs can be on whatever side they wind up on! They are identical. At least every one I've dealt with. If you have disassembled them and put 'em together wrong, they probably will not work.

If they are "LOCKED IN" you will not be able spin the "U" Joint at the knuckle. Even gently using a tool!

Sometimes the innards do not move when they are really nasty or worn. Even though you rotated them into place, one may not be engaged. You think you are in 4X4, put really, the transfer case's front Wheel Drive Motion is completely lost in the "Spinning Axle" which is not engaged.(Exactly the same as with a standard differential, one wheel spinning in the mud, other has no movement, 'cept, in this case, the spinning is at the end of your axle). Everything says you are in 4X4 but you AIN'T REALLY!

This was the reason for all of the front end testing, I thought maybe the hub(s) internally, might not be synchronizing with the axle splines. Which might still be a EZ fix, or an EZ replacement, and nothing torn up in the differential.

Usually a small amount of hard surface driving, won't hurt nothing. Over time it will.

You get lost. We might even discuss "Waypoints" later!

The Medic
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Wednesday, June 29th, 2011 AT 8:30 PM
Tiny
GWATTS1040
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Just have access to the jeep a short time each day until next week when I can take the wheels off to check the hubs. I did check the front drive shaft in free wheeling and it turns easily with no binding or noise. Drove it again in free wheeling and noticed it primarly makes noise when turning at any speed. Could the hubs partialy engage during the turn and become free again driving straight?
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Thursday, June 30th, 2011 AT 4:10 AM
Tiny
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Where the heck have you been!

I doubt they partially engage, I think they would make racket constantly

Also check the Knuckle "U" Joints sorta the best way you can, similar to the driveshaft "U" Joints, for slop at the bearing caps.I gotta change mine soon!

Do you have positive traction? To check, raise the front wheels off the ground. Lock in the hubs. Hold the driveshaft still. Turn One wheel, if the other one moves in the same direction. You have positive traction. If it rotates the opposite direction, you have a Standard differential

Do the same in the rear, to determine whether it's standard or positive traction

Let me know what you got, and where.

Are you really sure it's the front end, or could it be in the transfer case?

Another thing you might try is to completely remove the rear drive shaft, then drive in 4 Low and 4 High, Forward and reverse.

Are your rotors, calipers, and pads in good shape and bolts, and lug nuts are tight?

Have you raised the wheels and "Hugged" them, up and down, left and right. Feeling for sloppy bearings?

What about wheel stops, are they adjusted right, and your tires aren't dragging the frame, etc on turns?

I know I've slung a lot on you, but we gotta find out what affects it or not, to pin it down

Keep on eliminating, let me know your results!

The Medic
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Thursday, June 30th, 2011 AT 5:14 AM
Tiny
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CAME ACROSS YOUR POST WHILE LOOKING FOR SOMETHING

WHAT DID YOU FINALLY FIND OUT WAS THE PROBLEM?

THE MEDIC
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Sunday, April 10th, 2016 AT 7:23 PM

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