Stovebolt.com Forums The Parking Lot '60-'66 Trucks Steering Linkages Torque Specs

My son and I have rebuilt the steering of a 1963 GMC C10. However, we're having trouble finding all the torque specs we need to finish the job. I was hoping that someone on this forum might be able to help ...

From the manuals we have, we've been able to find some of the specs, but we're missing the torque specs for the pitman and idler arms. I'm attaching a diagram to illustrate. Any help would be very much appreciated. Thank you.

I have a 1963 service manual. I looked through the suspension and steering sections as well as the charts in the back, and did not see any torque specifications for the pitman arm or the idler arm.

Thanks for looking, Lugnutz. We have both the Service Manual and the Factory Assembly Manual, and neither seems to have the torque specs. I'm wondering where else we can look ...

I would go by torque specs based on the size of the bolt. The two on on the center tie rods would probably be the same as the ones on the spindle arms (23-49 lb-ft.)

Kevin, that was my first thought a few days ago and I even posted it. Then deleted. I believe those involve tapered and splined and cotter pins. The bolt charts are for clamping force. As for breaking the bolt, that is a materials strength calc. So I searched the internet for 55-59 and 67-72.

In my opinion: The cottor pin keeps it "safe" and the torque seats the taper or tapered splines, depending on the joint. Depending on if a lock washer is used on the pitman nut. Best average internet "info" was about 65 Ft lbs for idler and 120-140 for pitman.

Symeon: maybe a 60-66 GMC manual will have it. Also search Moog suspension. You can tighten them too tight and cause problems. I do not know if the numbers I gave are correct. Kevin has good numbers also. It depends on which idler joint....to frame or to another arm. I believe the low numbers are rod to rod as kevin says, and higher for "to frame".

I.E. Ref: I don't know size of pitman shaft but if you look up 7/8 on a bolt chart you get big numbers. As I said the pitman is snugging a spline on spline with a nut and lock washer. The others are non spline, tapered shafts with castle nut and cotter pins. With grease boots and ball ends. If a person can't find the info, you have to interpolate with era before and era after maybe.... and use info from similar joints as Kevin says. In my 1963 Chevy Truck Shop Manual it mentions 45 Ft Lbs for the steering joints.

Ken, I couldn't tell from the diagram whether all of the fasteners were for tapered rod ends. I agree that it might be too much torque if going by the thread diameter. I know that the splined connection on my '51 has no cotter pin, just a nut and lock washer also. I'd have to look it up for the torque on that (if it's available), but I do know that it was TIGHT when I removed it. Some of that may have been from the rust molecules holding hands. [on edit] for AD trucks the torque required for the pitman arm nut is 90-100 ft-lb. It uses a 3/4" diameter thread. Here [boltdepot.com] is a reference for torque values by bolt sizes. A grade 5 3/4" fine thread is listed at 223 ft-lb. The pinion nut really doesn't need that much as it' job is to hold the arm on and engaged with the splines.

Thanks everyone for your replies! It was really helpful to learn more about what normal torque specs look like for this part of the truck and what the different bolt threads are rated to take.

Over the weekend my son and I got the steering assembly setup using the advice offered.