Help needed with Toe In

[32sbct]

I just completed a full rebuild of my steering systems, full rebuild of the steering box, new pitman arm, rebuilt bellcrank, rebuilt drag link, new tie rods. I have previously rebuilt the axles and steering knuckles so everything is new.

I set the bellcrank, wheels, and pitman arm based on a post from Wes I found using a search. Everything was done per those instructions and everything looks good. Front tires are straight with the rears, bell crank is 90 degrees from front axle, pitman arm is in the correct position so that the wheel has the same number of turns left or right, etc.

So now I'm the point to set the toe in. I know the spec is 3/32 to 3/16 but as measured from what point I don't know. I've searched the manuals, the archives and on line and I'm afraid I just don't understand what I'm supposed to do or how I'm supposed to do it.

I took some measurements 13.5 inches off the floor from the center mold line of each tire left and right. The front was 49 inches and measuring from the same spot on the backside of the front tires I get 49.5 inches. A measurement across the very top of the tires is 49 and 15/16.

I know toe in is set by adjusting the tie rods but I'm not sure exactly how to do that or how much to adjust on either side. I am usually reasonable with mechanical issues but this one has me confused. I really want to get this tightened up and completed so I can move on to the trans and diff.

Thanks

[acengraver]

I don't know what Jeep you have but the procedure is covered in the TM9-8014, Pages 265-266 for the M38A1. It also shows the tool used for the measurement. I home-made one from a spring loaded shower curtain rod and some jack chain. It worked pretty well. It should work for any Jeep.

[capescw]

The 'toe-in' is the "front of tire-rear of tire" difference in tracking between the two front wheels. Your first quoted measurement:

"I took some measurements 13.5 inches off the floor from the center mold line of each tire left and right. The front was 49 inches and measuring from the same spot on the backside of the front tires I get 49.5 inches."

was the correct technique, but the wrong result (1/2 inch). You can achieve the measurement with a tape measure, as you're after the DIFFERENCE in readings, not the absolute measurement, TM 9-8012, page 269, as you stated, 3/32 to 3/16 inch

[wesk]

Assuming this is all completed correctly beforehand.
1-Steering gear is centered and steering wheel has equal Number of turns from center available.
2-Steering bellcrank is set at 90 degrees.
3-Using a straight edge along the outboard sides of the two left tires and then the two right tires determine both front wheels are straight ahead of their rear wheel and exactly parallel to it. You use the tie rod on that particular side to move the front of the wheeel left and right as needed to square it with it's rear wheel.
4-Wheel bearings are correct setting.
5-Tire size and pressure are the same.

With the weight of the complete jeep on the wheels, roll it forward a couple of feet. This will remove any slop.

Measure the distance between the inboard edge of the front rims about 45 degrees up from the low point of the rim.

Make the same measurement at the back inboard side of the rims at the same 45 degree point.

As you have already noted the front distance should be between 3/32" and 3/16" shorter then the rear distances. If it is outside this limit then make the necessary adjustment to the right (pass) side tie rod only.

[32sbct]

Thanks all for your replies. Wes I did complete all 5 steps you have listed. I will remeasure tomorrow using the rim as opposed to the tire and proceed from there. If I have to reduce the difference in measurement, I assume I will need to lengthen the passenger side tie rod. Correct?

[wesk]

Yes and if you have to increase the measurement then you would shorten the right (PASS) side tie rod.

The civilian service manual makes it a lot simpler. They simply square the front wheels with their back wheels then shorten both tie rods one half turn! Which is what I do rather then putzing back and forth with improvised measuring tools.