1953 M38A1 Front End Death Wobble

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dgmond
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1953 M38A1 Front End Death Wobble

Post by dgmond »

OK, my 1953 M38A1 has developed a front end Death Wobble. What could be the primary cause? Front bearings have been repacked, tie rods and steering is tight. Tires and shocks are good. I mean this thing scares the OD green right out of me.
southpw
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Post by southpw »

I see this is your first post..... Welcome to Willys jeeps.

Posting a question in the "For Sale" section is not going to get you very far. Your thread should have been started in Technical section. I'm sure Admin will move it for you.
1952 M38 project
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OKCM38CDN
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Post by OKCM38CDN »

Check Tire Pressure too...
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Post by wesk »

If you are 100% positive that wheel bearing adjustment is correct and all steering linkage and the steering gear box are in good shape and Positively not the fault then that only leaves the steering pivot bearings (king pins) in the steering knuckles. Low tire pressure aloe does not cause the death wobble. It can help it get started but is not the cause. The three culprits, loose wheel bearings, loose steering components and loose pivot bearings are the choices you have.
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dgmond
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Post by dgmond »

Thank you all. Sorry about posting in the wrong place. It was my first. :) OK since I posted, I had all tires inspected and rebalanced. Did a lot of research and I think it might be the king pins. But to be sure I decided to just start rebuilding the whole front end. I want to order a steering bell crank but am confused. All they offer is the 7/8 inch rebuild kit. Will that work on original equipment? Well let me put it this way, "I am asking you all is what would you do in my place"? Well beside throw a big BBQ when I am done.
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dgmond
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Post by dgmond »

southpw wrote:I see this is your first post..... Welcome to Willys jeeps.

Posting a question in the "For Sale" section is not going to get you very far. Your thread should have been started in Technical section. I'm sure Admin will move it for you.
Thank you
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Post by skyjeep50 »

If you use the "search" function you can read probably hundreds of threads on the same subject. Before you start ordering parts, make sure you know what you have is needing replacement. Do an assessment of the entire steering system to see what is worn. Start by looking through the technical manuals in the "Downloads" section of this website for specifications for parts. Order/buy parts from knowledgeable dealers for military vehicles - many times the local auto parts store is not going to be able to help very much as these vehicles aren't in their catalogs. Some parts do not interchange with other Jeep models. If you are trying to fix just "death wobble" I'd suggest adjusting king pin bearing pre-load first unless there are other obvious issues.
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Post by dgmond »

Thanks, I did start looking at the technical manuals this morning. Great thing you did there. Now I don't have to go crazy looking for and buying manuals. In my rush to get the M38A1 going, I did some short cuts. But I felt the front end was going to give out eventually. Might as well get it done now. Thank you for your help on this.
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Post by oilleaker1 »

Items to check after your wheels aren't bent are: bellcrank is not moving, knuckle bearings and races aren't worn out, and steering box bushings and worm/sector wear. Any slack from the steering box to the wheels, that lets movement happen will allow the wobble to take place. Especially when going through chuck holes in the road or bumping up over rocks in the road. You also need to shim those knuckle bearings so the arm takes some tension to move or rotate the knuckle. Cheap chi con bellcrank kits are a waste of your money. John
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dgmond
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Post by dgmond »

Thanks John, that's to Willy's Military Jeeps and other websites I gather a whole bunch of information about what needs to be done. Wow, its a lot, but I already have most of the parts ordered and have the labor covered. I do thank you for your help, And yep, I am picking about how to rebuild the front end. I don't want to ever experience the Death Wobble again. ~Darrell
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Post by BullRun »

Check your front springs too... on some old 4x4 vehicles when the front springs are sometimes replaced with the wrong size or load rating the vehicles develop the death wobble too.
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dgmond
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Post by dgmond »

Well the shocks, tires and leaf springs checked out. The Bell Crank is shot and driver side king pin is bad. I decided to rebuild the whole front end. Thank you all for the help.
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