steering issue

[Jake266]

My 1951 M-38 has a real bad steering wobble when speeds reach close to 35mph. I replaced the steering box with a rebuilt one from CA. Any ideas where I can turn from there?
Thanks.

[wesk]

Do a proper complete front end inspection. Get the book out and go step by step. Get a helper to hold things still when you are moving the various parts to check for slop. Complete means COMPLETE all steering component joints, wheel bearings and knuckle turning tension and knuckle pivot bearing play. If you do not understand any part of this then for your safety as well as that of others take it to a reputable front end shop.
_________________
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.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[Bretto]

Could be a number of things. kingpin bearings, tie rod ends, worn bell crank bearings or ball, draglink. Could be the new box and parts. Have you verified its all snug and no movement between the sector shaft and the worm gear or bushings? Having listed about all the parts, best to have someonemove the steering wheel while you take a look at all the moving joints for slop.
_________________
Brett
'51 M38
PHOTO DIARY OF MY BUILD

[Jake266]

WesK and Bretto,
Thanks for the information. I think I will take her to a good Jeep man here in town who is known for his knowledge and mechanical skills. If I try to determine the problem I'll probably cause more harm than good. I just want her safe on the roads for when the weather gets better.
At least I now know what to look for when I take her in to the shop.
Thanks again.

[artificer]

Never forget the simple stuff like wheel balancing
_________________
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND

[Cacti_Ken]

I balanced my wheels/tires when I had them mounted, only because it was a habit to do that. But I wonder, would an unbalanced wheel be noticed at 45mph?
_________________
Tropical Veteran
35th Inf. Reg. "CACTI" 4th I.D. VN
Amateur Radio K5XOM

[artificer]

[wesk]

Ken,
A very heavily unbalanced wheel may be noticeable rolling up to stop.

The proverbial death wobble is usually related to knuckle pivot bearing wear and / or incorrect knuckle steering tension. It is usually triggered by a pot hole or rail road track type encounters and can only be stopped by applying the brakes and most often also slowing down. Loose steering components can also behave well until they encounter the same road conditions and then they show themselves as a serious wobble. The wobble itself is usually a lateral movement (you can feel and see the steering wheel trying to move rapidly left and right) and not so often a hop caused by serious wheel imbalance. Belted tires can slip a belt and cause very similar symptoms.
_________________
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.php?set_albumName=Wes-Knettle&op=modload&name=gallery&file=index&include=view_album.php

[Phil4280]

Have seen a jeep some time back with its front wheels wobbling like a shopping trolly... boiled down to the caster angle.

Phil...
_________________
Ex Aust Army Engineer ;
M3 Stuart Lt tank,1942 C8A HUW, Ex mil Landrovers,1ton Humber & Austin Champ, Mk1 Ferret scoutcar,trailers & Miltary radios.
Current projects:- M606A3 and 1958 Landrover 106mm RCL gun buggy
Latest addition M38A1 date e

[carioca]

Dear Wes K,

I have a M-38 here in Rio de Janeiro.
That "death wobble" is almost killing me.
Trying to solve that I have done the following :

a) Replaced the knuckle pivot bearing to new ones.
b) Adjusted knuckle steering to 6,5 kg of tension.
c) Replaced all shackles, pins a bushing ( all 4 wheels)
d) Rearched all leaf springs ( 4 wheels )
e) Replaced all tie rod ends
f) Adjusted draglink connections and bell crank gaps


What I have still to do:

I still have a defective steering box with a 13 cm ( 5 inch ) arch play measured at the steering wheel.

I did not balance all the wheels yet.

I friend told me that the only solution to correct the wobble is to add a wedge between the front axel and its leaf spring in order to correct the caster angle.

Could you advise me on that please.

( sorry if my english is somewhat hard to understand )

Regards,

Carioca

[artificer]

If you have any slop in the steering in the drag link & bell crank if your model has one plus like 120mm [5"] 2 the steering wheel you don't have far to look. And wheel balance being out can also be a major contributing factor.
_________________
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND

[carioca]

Hello Artificer,

Thanks to your info.

Does that procedure of using a wedge to correct the castor angle tells you something ? I do not know if it could help stopping the "death wobble" or it is just rubbish.

Regards from Rio ( 38 centigrades today ...and getting warm )

[artificer]

Caster wedges will not stop the condition you [& others] are talking about. Caster wedges are used so the vehicle will not tend to "wander" if that is apparent when you have fixed what is causeing "death wobble"....not unique to Jeeps but also Toyotas & Land Rovers [plus probably other 4wd's] when excess wear is apparent.
_________________
John GIBBINS
ASE Master Medium/Heavy Truck & Auto Technician 2002 USA
Licensed Motor Mechanic NSW # MVIC 49593 Current
YOU CAN'T TROUBLESHOOT WHAT YOU DON'T UNDERSTAND

[carioca]

Ok.

I will repair the steering box and balance the wheels before trying anything else.

Thanks again,


Carioca