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Old 11-05-2018, 11:05 PM   #1
71CHEVYSHORTBED402
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Installed leaf springs & axle today, but questions

My son and I installed drop springs and the axle today. Pretty excited about it, because it offers some assembly as the painter stares at my oil pan each day in prison. Hopefully it's done within three seasons, two passed already

I haven't built the entire rear end yet, so no tires and that. Anyway, all the hardware is new, and I tightened the eye bolts and U-bolts down. I even leveraged using a pipe to squeeze the shackles. All the bolts are tight, but as it sits on the frame, there is more to take. I plan to torque them when the tires are on the ground. I assume there's more to take when the tires are on the ground.

Questions:

1. Was it an error to tighten the bolts down in this manner? In other terms, should all the bolts be snug only when the weight is dropped onto the tires?

2. If the bolts should be snug only, no problem, my wrench goes in reverse too. But what you figure I did to the distorted torque and U-bolt nuts? Frankly, the plan is to replace all the torque nuts, but I don't have spare 9/16" torque nuts at hand, never mind spare U-bolt nuts. I'd rather eat the error and expense if it's best to replace the new nuts with......new nuts.

Edit 3.Just thought of it, I'm not sure what amount of play is acceptable between the eye bushing in the leaf spring and the top of the shackle. As mentioned, I leveraged using a pipe to squeeze the shackles. But there remains about 1/8" play between the end of the bushing and shackle. My son and I believe it's right, but I can't say for sure. These are C10 shackles, but........I'll take a picture, post it up.

All input appreciated, thanks
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71 C10 Custom Deluxe, SWB, fleet, 402/400TH, A/C...Resource intensive

72 Cheyenne Super, LWB, fleet, C20, 402/400TH, A/C. Driver and tinker truck

Last edited by 71CHEVYSHORTBED402; 11-05-2018 at 11:58 PM.
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Old 11-06-2018, 01:20 PM   #2
B. W.
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Re: Installed leaf springs & axle today, but questions

1.Leave your spring eye bolts loose until on the ground & the body is on so it's sitting at it's static height. (I have a punch list after final assembly, checking these bolts is on that list)

2. Tighten the U- bolts & call 'em done.

3. The inner sleeve of your spring bushing should be longer than the rubber bushing itself. The inner sleeve should be tight against the shackle when the bolt is tightened. Some even have serrations on them to help them "bite".

If the inner sleeve is not touching with the bolt tightened you may have run out of threads on the bolt.
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Old 11-07-2018, 12:10 AM   #3
71CHEVYSHORTBED402
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Re: Installed leaf springs & axle today, but questions

Quote:
Originally Posted by B. W. View Post
1.Leave your spring eye bolts loose until on the ground & the body is on so it's sitting at it's static height. (I have a punch list after final assembly, checking these bolts is on that list)

2. Tighten the U- bolts & call 'em done.

3. The inner sleeve of your spring bushing should be longer than the rubber bushing itself. The inner sleeve should be tight against the shackle when the bolt is tightened. Some even have serrations on them to help them "bite".

If the inner sleeve is not touching with the bolt tightened you may have run out of threads on the bolt.
Got it, eye bushings loose, torque the U-bolts, build and drop, and then torque the bushings. Good idea on the punch list, I've been meaning to start one.

I have those bushings, but I don't think I ran out of thread. Seems there's 1.1/2 of thread, and I only see about 3/4" counting the nut. I may have to pull a bolt and see. Perhaps I'll pull the shackles as well, see if they'll close some in a vise.

EDIT: With another look B.W., I think the shackles are right. Here's a picture of the eye bushing inside the front mount. This was a tight fit just to slide it in, but it appears to have the same "gap" as the shackles, which as you pointed out, may not be a gap at all. EDIT x2: I just thought to measure the inside diameter on top of the shackle. Closer than original (2.11/16" Vs 2.3/4") and the new springs are the same width as the old. Thanks B.W.
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71 C10 Custom Deluxe, SWB, fleet, 402/400TH, A/C...Resource intensive

72 Cheyenne Super, LWB, fleet, C20, 402/400TH, A/C. Driver and tinker truck

Last edited by 71CHEVYSHORTBED402; 11-07-2018 at 01:06 AM.
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Old 11-07-2018, 08:15 PM   #4
71CHEVYSHORTBED402
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Re: Installed leaf springs & axle today, but questions

On a side, assuming his specs. are right, this is very nice: http://www.chuckschevytruckpages.com...que_specs.html

Edit: He's not specific about the rear suspension, c-10 vs other. That and the original U-bolts on my C10 were 1/2". They were replaced with 9/16". Looking at his specs of 150 FT. POUNDS, I can only assume he's referring to grade 8 9/16" U-bolts, but it strikes me 150 is too much for even that. I put 50 lbs. on. While there's more to take, it feels close.

This might be a better source. That said, I think I see why a lot of guys say to tighten until you know it's right as opposed someone's specified torque, too many variables: https://www.suspensionspecialists.co...nformation.pdf

Per a phone call with this group, the max. torque setting for 9/16" grade 8 U-bolts with the upper and lower plates is 100 ft. lbs. Their page reads 93 ft. lbs., but perhaps a decent range: https://www.autoandtrucksprings.com/...-u-bolt-torque
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71 C10 Custom Deluxe, SWB, fleet, 402/400TH, A/C...Resource intensive

72 Cheyenne Super, LWB, fleet, C20, 402/400TH, A/C. Driver and tinker truck

Last edited by 71CHEVYSHORTBED402; 11-08-2018 at 04:25 PM.
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