Front wheels wobble while driving

1stSgtUSMC · Post by **1stSgtUSMC** » Sun Jun 21, 2020 4:25 am

Is it normal for my front wheel to woble when I hit a bump when going 35-45mph? I noice it when im going around a curve and hit a bump in the road as well. I would imagine this is not the norm, what do I need to replace/ repair to fix this issue? I recently replace the front outter bearings and cups hoping that would solve tthis issue with no luck even though the bearings needed to be replaced. Thank you in advance.

S/F
Kevin

Post by **wesk** » Sun Jun 21, 2020 6:35 am

Yes, that is called the "DEATH WOBBLE" and it is a very common issue with our old jeeps. Wheel bearings can be a part of the problem but the real culprit is usually the king pin bearings as most people know them or the upper and lower steering knuckle pivot bearings as we know them.

If you will take a minute and read Section IV on page 72 of your M38's Operator's Manual, TM 9-8012, 'TROUBLESHOOTING' you will find on page 103 a topic called "f. Shimmy at low speeds" where there are 6 possible causes listed.
Check each possible culprit before spending a lot of time or money on only one item.

Items "D & E" are the usual culprits.

To make a quick check you jack the front axle off the ground with a floor jack under the pumpkin. Grab the top of the tire with one hand and the bottom of the tire with the other hand and rock the tire/wheel assy in and out and if the top edge of the tire moves towards and away from the axle more than 2 to 5 degrees, adjust or replace the bearings. I try to always change them as a set. Again the instructions are at your finger tips in your TM 9-8012 page 262 Paragraph 230.

1stSgtUSMC · Post by **1stSgtUSMC** » Sun Jun 21, 2020 2:14 pm

you wouldnt be so kind to give me the timken part number (D&E) would you?

Post by **wesk** » Sun Jun 21, 2020 9:01 pm

I was hoping you would follow my lead and open the manuals. If you do not currently own them they are free to download in PDF format here on our "Downloads" page. All 4 maintenance manuals and the parts manual.

http://www.willysmjeeps.com/v2/modules. ... =Downloads

The ordnance PN's are on page 221 of the ORD 9 SNL G-740.

Cone: 705381
Cup: 706813

If you locate a copy of the ORD 8 SNL G-740 you'll find the FSN's listed on page 101.

Cone: 3110-100-3132 or to upgrade to the current NSN just add the 00 after 3110-00-100-3132

Cup: 3010-100-0509

I found the Timken # several years ago by simply googling "3110-00-100-3132" and visiting the site hits. IE: https://www.wbparts.com/rfq/3110-00-100-3132.html

1stSgtUSMC · Post by **1stSgtUSMC** » Mon Jun 22, 2020 6:57 am

and uless I am reading this wrong....I need 2 cone and bearing sets per tire..total of 4.

Post by **wesk** » Mon Jun 22, 2020 7:03 am

Yes. The proper installation instructions are in the TM 9-8014 pages 253 thru 257. Special tools needed are a spring scale and Hub nut socket.

1stSgtUSMC · Post by **1stSgtUSMC** » Mon Jun 22, 2020 7:17 am

I have the hub nut socket....no spring scale.....Am I getting over my head?

1stSgtUSMC · Post by **1stSgtUSMC** » Mon Jun 22, 2020 7:21 am

I also see a seal "Z". I am assuming I will need to replace that as awell?

Post by **wesk** » Mon Jun 22, 2020 7:39 am

You'll find the instructions for the dis-assembly of the rest of the front hub & steering parts on pages 245 thru 252. The industry standard service life of rubber and neoprene parts is 8 to 10 years. Since these jeeps are well over 50 years old it is common practice to replace all seals that are removed or exposed during a repair action.

1stSgtUSMC · Post by **1stSgtUSMC** » Mon Jun 22, 2020 9:27 am

where does one buy a spring scale?

1stSgtUSMC · Post by **1stSgtUSMC** » Mon Jun 22, 2020 9:48 am

I can not find the part number for the "Z" seal...can you assist with this?

Post by **wesk** » Mon Jun 22, 2020 10:13 am

where does one buy a spring scale?

Just google Spring scale.

I can not find the part number for the "Z" seal

That parts page illustration is for a WWII MB not an M38. Your ORD 9 SNL G-740 parts manual illustration for that hub is where you should be looking. In that manual Fig 10-4 does not show seal Z because on the the later axles that seal is at the inner end of the axle shaft. The differential must be removed to replace that seal. Look at Fig 10-3 in your M38's Parts Manual. The seal we are talking about is B.

Most hobbyist prefer not to attempt the diff removal because the set-up and shimming required on installation is usually beyond their expertise. However each time that axle shaft is removed the odds are that the seal will be a bit damaged during each installation. So the choice is yours but most hobbyists ignore the age of that seal until they start getting diff gear oil on their brake shoes.

jnissen · Post by **jnissen** » Mon Jun 22, 2020 10:55 am

Spring scale is a fishing scale. Not overly expensive or complex!

The seals on the knuckle vary. We used new rubber and reused the aluminum style backing plates. I’ve seen a variety of different solutions sold. We preferred the OEM type but upgraded to a neoprene seal In place of the felt.

BTW good time to pick up the proper lube. Check other posts as it’s detailed under knuckle lube. Good time to also inspect your axles and be fix joints. Modern alternatives exist that use spicer joints (U-Joint) that are much less maintenance intensive.

1stSgtUSMC · Post by **1stSgtUSMC** » Mon Jun 22, 2020 11:30 am

tracking like a tank...I thought it was part of the bearing project that I am about to tackle.

1stSgtUSMC · Post by **1stSgtUSMC** » Fri Jul 10, 2020 4:34 pm

completed the job and Wes it is cured! thank you kind sir!

S/F
Kevin