GMCforum
For enthusiast of the Classic GMC Motorhome built from 1973 to 1978. A web-based mirror of the GMCnet mailing list.
Home » Public Forums » GMCnet » Steering box centering
[GMCnet] Re: Steering box centering [message #367362 is a reply to message #367360] Thu, 28 October 2021 16:16 Go to previous messageGo to previous message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma:
Senior Member
Greg,

Here's the best information you're likely to find about the GMC steering
box:
https://www.gmcmi.com/wp-content/uploads/2013/02/GMCMH-Steering-Box.pdf

From that, the GMC steering box is internally the same as the Saginaw box
used in most GM vehicles of the same generation EXCEPT that it has internal
stops to limit the travel of the pitman arm. Those stops are very
important because without them, the entire steering system can be severely
stressed. If you turn the steering wheel to its extreme travel then look
behind the wheel away from the turn direction, you'll find the ultimate
cause of that stress: The knuckle has on it a "stop" (a molded protruding
knob) which will be near or against a welded stop on the lower A-arm. With
the correct stops inside the steering box, those two should never touch.
Without those stops, that's the "steering lock". With the hydraulic force
available, there can be a LOT of force exerted on all of the steering
linkage. Probably the most severe is right there on the lower ball joint.
Measure the distance from the pivot of the ball joint to the end of the arm
on the knuckle. Now compare that to the distance from the stops to the
pivot of the ball joint. As a WAG, I'd say it's about 3 times as far from
the end of the arm (lever) as from the stop (fulcrum), so that the force on
the steering linkage (100+lbf?) becomes 300+lbf? on the ball joint. Not
good! You want those stops in the steering box!

HTH,

Ken H.

On Thu, Oct 28, 2021 at 4:48 PM Greg Crawford
wrote:

> So I'm fighting a back injury right now, and I'm not able to do much. But
> today I went out to the coach and checked the amount of turns lock to lock.
> It looks like about 3-1/4 turns. So, from Jim Hupy, this is not a factory
> steering box.
>
> Am I screwed here? Does this box have the infamous "high spot" that
> corresponds with the input shaft flat aligned with the cover axis?
>
> Or are all bets off?
>
> It does require more hand movement than I would like to keep it straight
> going down the road. I have not yet removed the intermediate shaft to
> confirm
> the position of the input shaft flat, but since the steering wheel is out,
> I'm pretty sure that everything needs adjustment.
> --
> Greg Crawford
> KM4ZCR
> Knoxville, TN
>
> "Ruby Sue"
> 1977 Royale
> Rear Bath
> 403 Engine
> American Eagle Wheels
> Early Version Alex Sirum Quad bags
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:

Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach

Report message to a moderator

[Message index]
 
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Read Message
Previous Topic: [GMCnet] Tid Bit. The stock fan clutch
Next Topic: WEATHER MAP
Goto Forum:
  


Current Time: Tue Jul 02 22:21:44 CDT 2024

Total time taken to generate the page: 0.00688 seconds
.:: Contact :: Home ::.

Powered by: FUDforum 3.1.1.
Copyright ©2001-2021 FUDforum Bulletin Board Software