The Stovebolt Site Forums The Shop Area Driveline A couple 3100 leaf spring questions

I could try that…..

However, it’s been a year and I partially disassembled the spring before telling them anything about it.

I'm sure they'd understand that people order lots of parts for a restoration long before they're ever installed. I'd at least attempt talking to them on the phone. If they made a mistake in the manufacturing process that renders the product unusable, it shouldn't matter how long it's been.

They should also understand that you attempted to rectify the problem yourself so as not to trouble them with it. You haven't ruined anything - the bolts are nothing.

Worth a try.

Switching topic just slightly. I tore apart only one side and I’m gonna use the one good spring to put things back together on that side.

Is this a logical sequence to do that?



I’d also like to measure and correct with shims, if necessary, the pinion angle while I’m going through all this hassle. Do i have to fully tighten u bolts to get an accurate measurement?

You just have to tighten them enough to make things snug. Do you think you have a problem with your pinion angle? Is it howling or does it look wrong? Have you measured it?

You know to have the bed all together, fenders on and sitting on the ground, yes?

The truck when I got it had badly wasted u joints. Pinion leaks. It doesn’t howl. I’d just like to be sure and not tear things apart twice. The rear end swap shows signs of being a “farmer” job which makes me wonder.

Shackles were in such sad shape I didn’t know if I’d get an accurate number if I did it before the spring replacement. Perhaps that’s irrelevant. I’m learning as I go here.

Truck is fully assembled.

If it is assembled and sitting on the ground (so that you could drive it) and with good u joints, just measure the angle between the crankshaft and the driveshaft and mark that down. You can use the bottom of the engine block where the oil pan mounts. That will be a straight line with the crankshaft. Or you can rotate the u joint flange (end of transmission yoke) upright and come off that 90 degrees to get your line. Once you have the angle between the crankshaft and the driveshaft line measured, then do the same at the differential and add ~1 degree at the differential to take into consideration spring wrap-up. Ie, if you get 3 degrees at the transmission and 3 degrees at the differential, make your angle at the differential somewhere between 3.5 and 4 degrees. The wrap-up allowance is something you'll get all manners of opinions about, but over the years I've learned this is something you do not want to ignore on a pickup if you have a stock setup. Fortunately the AD truck was designed with spring under axle. That helps a bit as spring over axle always makes wrap-up worse. And wrap-up occurs both on acceleration and deceleration. The heavier the vehicle is, the worse the wrap-up will be and the more tendency there'll be for wrap-up while driving. If you have 800 pounds of something in your bed then even with really tough springs like the AD has, you'll get spring distortion every time you take off and stop unless you take off and stop very very slowly and just regular driving will cause the spring to flex also. Good luck.

There actually a few phone applications you can use to verify the right angles.
Getting it right is key and you actually want a .5 degree difference not exactly 0.0 etc.
the app i use is from Tremec I just fire it up. put phone on bottom of engine, drive shaft and rear diff, three button pushes and it calculates its all and tells me which ones are out if needed.
Like seeing 3 greens when I check it.

FYI some of the internet videos get it completely wrong on how to calculate it. some think as long as its just within three degrees of each other its ok even if its 20 degree angles. steering wheel shaft is one thing but a drive shaft at thousands of RPMs is another.

And the wrap comment is dead on. MY task force went thru 3 universal joints until I determined how much wrap was going on and fixed the springs up.

The goofy spring is now repaired. Flipped that one leaf around and all is good.

Thanks for all the help!

Cool. Thanks for closing the loop on that.

Went to mount the spring on the one side I have torn down. Front eye bolt mount fought me….hard. The frame mount must have been squeezed together too much from before.

Finally got the bolt through and called it a night.

When I do the other side I will work harder ahead of time to get it spread out to accept the spring eye.

Back to overthinking things.

Went to hang the other end of the new spring on my new shackle tonight. Threaded bushing in the spring had some buggered up threads. No big deal, I have extra bushings since I bought complete shackle kit. Pushed the existing out with the new one and a ball joint press. Used anti seize on the new.

Then I got to thinking….might be bad deal if the bushing spins inside the spring eye, rather than the threaded shackle pin inside the bushing. (Hopefully that makes sense). Last couple turns of the press were awful easy. Maybe shouldn’t have used the anti-seize.

Should I take the bushing back out and loctite it or something? Or don’t sweat it?

I wouldn't sweat it. As long as you keep the shackles greased up, it should be fine.

I doubt if the OD of the pressed in bushing is going to turn. As Kevin Said, “Don’t sweat it”!

Should be putting the truck back down on 4 wheels today for the first time in a few weeks. Springs are in. Need to get truck on its own weight and torque everything.

How much extra should I leave on the u bolts when I cut them short?

When I installed the open drive shaft and new spring perches on the '47 I left them long. I was told to drive it a while, re-torque them and use a cutoff wheel to trim them up with a 1/4" of threads exposed below the nuts.

JW51 In the gravel road days those tail threads would be all beat up,our spring shop has a big sign says to tighten 3 times. Well on big off road trucks I tightened every time I saw em for a while !! Using a big flex handle. 1/4 inch be fine,might leave em long for a while till you know your done. On your shackel worry why don't you put a mark on your part (ink marker) grease it ...keep an eye on it,don't think it's goonna move.