M38 Popping noise in reverse?

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redrad
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M38 Popping noise in reverse?

Post by redrad »

While backing up and turning with front hubs locked in and front wheel drive engaged, I hear a hard popping noise coming from the front end. I have re greased ball joints and tried to find any thing loose or looks wrong but dont know what may be the problem. I hear nothing wrong backing up with hubs unlocked and out of front wheel drive. Any ideas what may be causing this or what to check next.

Thanks in advance for in advise.
Johnny D
1951 M38 Ser#1723
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wesk
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Post by wesk »

Have you put the jeep on a hoist, ran the engine and engaged the 4WD & hubs in reverse?
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
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redrad
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Post by redrad »

No I have not, but I will in the next few weeks. What will I will be looking for?
Johnny D
1951 M38 Ser#1723
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wesk
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Post by wesk »

The source of the noise.
Wes K
45 MB, 51 M38, 54 M37, 66 M101A1, 60 CJ5, 76 DJ5D, 47Bantam T3-C & 5? M100

Mjeeps photo album: http://www.willysmjeeps.com/v2/modules. ... _album.php
RonD2
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Post by RonD2 »

Hi Johnny,
Before this surfaced, have you ever had your front steering knuckles and axles apart to inspect and service them?
Which type axle joints do you have? (The turn stop angle has to be adjusted differently for each type).

Curious you only have noise in reverse.
Please keep us posted what you discover!

Good luck!
Ron D.
1951 M38 Unknown Serial Number
1951 M100 Dunbar Kapple 01169903 dod 5-51

“The only good sports car that America ever made was the Jeep."
--- Enzo Ferrari

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redrad
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Post by redrad »

Well I put the Jeep up on jacks and here are the results.

Test1. Started up motor put in reverse no popping nose. Turned wheel all the way left and right no popping.

Test 2. Engaged front axle performed same tests same result.

Test 3. Locked in front wheel hubs, performed same tests no popping.

I have rebuilt the front left wheel, new brake shoes, wheel cylinder, bearings and races, axle spindle, seals and knuckle lube.

I guess now will tear into passenger side and see if there is a problem.
Johnny D
1951 M38 Ser#1723
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mdainsd
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Post by mdainsd »

Jacking it up and running it may not reveal the cause. reason: when doing this, there is no load on the drive components, you can't put any energy into the system to get it to recreate the noise.
'52 Dodge M37, '42 GPW, '48 FrankenJeep CJ2A/M38, '50 CJV-35(U), '51 M38, '42 WC-57 Command Car, '44 WC-51 Weapons , (2) M1941 Sperry 60" Anti-Aircraft Searchlights, John Deere M-gator, '44 White M3A1 Scout Car
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keats
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Post by keats »

worn axle joints are suspect.
Gary Keating
1949 C3A, 1952 M38,
1954 M170, 1957 Cj3B
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