Thread/pitch size for stock u-bolts

[DuaneD]

Guys,
Ater taking longer that I ever imaged, I got off the four u-bolts from my 85 CJ. Before I put them back on, I would like to run a die over the u-bolts. Can anyone tell me the tread and pitch for these stock 1985 CJ8 u-bolts and nuts? Thanks,
Duane

[Jim_Lou]

They're either 1/2-20 or 9/16-18.

But they say you should never re-use axel U-bolts. They stretch and deform on the first tightening and woin't be as strong when tightened successive times.

I had a bolt shop make new 9/16 grade 8 bolts the last time I had the front axel off, and they were only about $30 a set, IIRC. 1/2" bolts can be gotten off the shelf at a trailer supply / camper store, and they're real cheap.

[mbalbritton]

are you talking Axle/Spring U-bolts or Driveshaft/Ujoint U-bolts?

[GoldToyBox]

I agree about not re-using old U-bolts but they aren't that cheap to have made around here it runs about $50 -$70 per axle (w/nuts&washers). About half that if pre made off the shelf.

[Jim_Lou]

I just looked up some old invoices - $29 for 4 custom-made 9/16" grade 8s. $17.00 for 4 off-the-shelf 1/2" from a trailer shop. Everything's higher at 7,000 feet. And in Granola Land.

I had some 1/2" grade 5s made also, but couldn't find the invoice for them.

[mbalbritton]

Originally Posted by GoldToyBox

I agree about not re-using old U-bolts but they aren't that cheap to have made around here it runs about $50 -$70 per axle (w/nuts&washers). About half that if pre made off the shelf.

CRAP!!! I'd be inclined to see if someone on here could have some made for you and shipped to you. If I still passed by the spring shop everyday that I got mine at I'd do it for you. my price was more inline with Jims. Or find an online dealer.

[DuaneD]

Thanks guys for the input. I need the u-bolts that hold my stock CJ8 (six leafs I think) springs to the Dana 30 axle. I am about an hour drive from a place where I could aquire or have u-bolts made. I noticed that 4WD has some for about $8 each. My initial thought was to run a die down over the threads on the u-bolts and replace the nuts and lock washers. Duane

[Jim_Lou]

I think it's worth $40 to put new bolts on it. And they should come with nuts and lock washers. I'm a little skeptical about the real need to replace them, but the consequences of having one come loose are pretty severe.

[LEVE]

It's a question of how much your life is worth. U-bolt threads deform for a reason. They deform to help lock the nut in place when properly torqued. Even if you chase the threads that won't restore the thread ability to deform, or restore the malleability of the base U-bolt metal.

So, let's say you chase the threads, install the U-bolt and nuts. What can happen? The U-bolt's already stretched to it's torque design limit. Now you'll reinstall nuts and stretch it even further. Will those threads deform and help lock the nuts? Yes, they likely will, but as they're part of the U-bolt material they'll deform, but not to spec.

Does that mean that you'll be tooling down the Interstate at 70MPH, or on the trail at full droop with a 35" tire spinning at 2000 RPM seeking to grip, and a U-bolt will drop off because the stress is too much.

Oh my heck, why worry... ain't there two U-bolts on each spring pack holding the axle? So it won't go anywhere ... right?

So I'll ask again, what's your life worth? After all you'll save a few bucks reusing the U-bolts.

For goodness sake folks, use your heads for something other than a hat rack and cut back on the donuts for a couple of days and pop for new U-bolts and nuts. If you don't value your life (and the lives of those who ride with you... and drive around you) who else will?

We just had a tread on the morality of insurance. Morality can extend to many aspects of life.... even U-bolt usage.

[DuaneD]

Ok LEVE, I am a sinner. I see the light. I have just gotten off the phone with the folks @ 4WD. They said they can ship into the Smoky Mountains from Buckeye land. I am saved. Thank you for the wisdom .