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monsterbronco
09-09-2011, 05:05
the truck:
86 Suburban, 3/4ton, 2 wheel drive. 75K miles

problem:
there is very little effort required to move the steering wheel.

this is great for maneuvering around parking lots and my driveway but just multiplies at highway speed. has made things a bit interesting at times.

the truck has been in my family since new and has always had very sensitive steering. I love the truck and cant bring myself to replace it with something newer.

new tirerod ends (inner and outer), balljoints are in good shape. tires are brand new and alignment was done with tires and tirerods.

this is not a "too much play" in the steering it is an over sensitivity. I bought a universal steering stabilizer from LMC truck last fall. It seemed to help some at slow speeds but not much a highway.

so my thoughts are,
-change to a smaller pulley on the pump
-pump from a different year truck
-stronger stabilizer dampener
-smaller steering wheel
-other thoughts

Sorry for the long post,
thanks for any help!
Wes

Edahall
09-09-2011, 06:25
I installed a smaller steering wheel on my 82 Suburban and it made a big difference on what you are describing. My 1990 Suburban doesn't exhibit this issue however, it's got a heavy Cummins 6BT in front and heavy wide tires.

chevytuff
09-09-2011, 21:45
Another thought but adjust at your own risk. On top of the steering box there is preload adjusting screw secured with a jamb nut.

The general consenus in the 4x4 realm is that over the years the gears in your steering system loosen up a bit, hence the easy effort to turn your steering wheel which is great for low speed manuevering but not so great for high speed driving. If you tighten the pre load nut a small amount you can adjust it back closer to factory specifications.

I did mine and the steering is now much better.

A more technical way of doing this is listed below.

Disclaimer: I did not compose these directions You should consult a FSM prior to attempting this procedure.



Steering box adjustment
The only way to properly adjust the steering box is to remove it from the vehicle.
Tools required: Inch pound torque wrench capable of readings under 20 inch pounds,
Spanner wrench. 5/8” end wrench to loosen the pitman shaft adjusting screw lock nut, 3/16”
Allen wrench to turn the pitman shaft adjusting screw
The setting up of the gearbox is quite simple using an inch pound torque wrench. Note:
Most click type inch pound torque wrenches only work above 20 in/lbs – this is too high for
our purposes.
1) Adjust the valve cartridge preload.
The pitman shaft adjustment screw and lock nut must
be completely backed off by loosening the retaining
nut and turning the Allen screw counterclockwise a
few turns.
Pump the power steering fluid from the inside of the
box by moving the pitman arm back and forth.
Loosen the adjuster plug locknut and, using a spanner
wrench, screw down the adjuster plug cartridge until
you get about four (4) in/lbs of preload measured at the input shaft. Then lock it down with
the lock nut.
2) Find the center of the movement by turning the input shaft halfway through the total
movement. To verify, when centered the plane of the machined surface of the side
adjustment plate will be parallel to, and in the same plane as, the flat spot on the input shaft.
3) With the in/lb torque wrench turning the input shaft a few degrees from center in both
directions turn the pitman shaft Allen adjustment screw until you read another 10 in/lbs to
see a total of 14 in/lbs at top dead center. These numbers are nominal and could be slightly
more or less. Using an inch-pound torque wrench to measure preload The alignment of these two machined surfaces is mandatory (top dead center), and must be held when
installing the box on the vehicle. This is important because the 10 in/lbs tight spot is only in contact for about 8 to 10 degrees of steering wheel movement in ether direction. If this true center is not maintained, you will have magnified movement through the steering system due to the machined clearance of the teeth of the rack and pinion without preload.

monsterbronco
09-12-2011, 09:21
Thanks, I will look for that adjustment and see what the FSM says about it as well.