NJTman

Anyone ever have the rivets loosen up on their front leaf springs, near the front bumper ?


I was under the truck today and found that the spring perch on the drivers side has actually loosened up and is moving around on the frame. Seems as though the rivets have failed on the underside. The frame seems to be in good shape, but the rivets are slopping around in their respective holes through the frame and perch plate.

Anyone ever seen this happen before ?



I'm going to cut the rivets out and install some new GR-8 bolts, sometime during the week.

Strange.......




T.

Richie O

When you do go up one size and drill new holes. You need holes that fit the bolts correct or they will always work loose. I would bet your holes are stretched out of round.

sooty

my axle was torn out a accident going down into a hillside culvert when i got the truck, i cut the parts from the other frame, and used grade 8 serrated bolts, enlarged to the next size, like richie o said, the serrations lock the bolt torque, and prevent movement.

ppiggppenn

That's the first I've heard of serrated bolts; do you need to thread the holes or are they self-tapping? I have a similar situation in rear with a box mounting bracket-to-frame attachment. Thx.

sooty

check hole measurement, if theres any slop at all, drill up one size, bolt cap and nut is flared, with serrations around the contact surfacethey go down and stay down, i get them from nutty bolts, hesperia calif. you should have a more local hardware specialist

NJTman

I would bet you are correct.

Thanks for the tips, guys. Most appreciated. Will follow the "upsizing procedure" as recommended.

T.

Philip

Most truck repair shops have the flanged bolts and nuts. They call them frame bolts.

I have replaced all the revits on both front spring hangers.

NJTman

You guys were correct... as expected.


The rivet was really distorted... as you can see.

Replaced it temporarily with a GR8 bolt, first resizing it up to 1/2", as it was slightly smaller.

Now to find new "frame bolts"

BTW... All I did was cut the head off and push it out with a pneumatic hammer. The distortion was there before I did anything.

Thanks Again ! All of your input is greatly appreciated, and this place is truly invaluable again....


T.

james1

I got under the truck tonight to change the oil and grease the multiple grease fittings and I saw that on the driver-side spring perch nearest the bumper one of the OEM rivets is missing the head -- sheared completely off and shiny steel showing.

What do I use to replace said rivet?

TIA.

thrashingcows

When I did the 4wd conversion on the crewcab I used some hardware from McMaster-Carr.....

They were 1/2"x20 flange head bolts, with flange head stover nuts.

Here are the part number from McMasterCarr...

92316A754 -Grade 8 Steel Flanged Hex Head Cap Screw, 1/2"-20 Thread, 1-1/2" Long, Fully Threaded

90949A037 - Black-phosphate Grade G Steel Flange Locknut, 1/2"-20 Thread Size, 3/4"w, 17/32"h Overall

comotionman

I disagree with this bolt selection. A bolt with an unthreaded shank just long enough to pass through the frame and spring hanger would be best. And this should be a close tolerance almost press fit.

thrashingcows

I know the hardware I chose is not the "best" hardware available, but couldn't afford the $7 per piece for the high end stuff. But since I was going to be needing 50 or more pieces I decided to compromise with the next "best" option, IMO.

I chose these so I could use the same bolt throughout the 4wd front end assembly. I believe though that the flange head bolt and nut will be far superior to a similar regular bolt, nut and separate washers in clamping force, and longevity.

james1

Thanks so much...


I agree. A serrated flange head bolt with a partially threaded shank would be perfect. But the unthreaded portion of the shank must be quite short -- like 3/8". And my rivet failure looks like classic "cup-and-cone" type failure, meaning the rivet failed from tensile stress rather than from shear stress -- indicating the replacement bolt should be at least Grade 8.

Soooo, a grade 8 serrated flange-head half-inch bolt with a very short section of unthreaded shank -- where do I find such a thing?

TIA.

thrashingcows

That was one of the things I found, short bolts are almost always threaded all the way.

Mcmaster-carr might have what your looking for?

james1

They do not appear to.

From what I can read, it seems important to utilize a flange bolt (a/k/a "frame bolt") and serrated flange bolts are preferable because they will resist turning. I suppose I could use an ordinary grade 8 hex head cap screw with serrated washers. McMaster-Carr appears to have those with short unthreaded shanks...

Ideally, I would find a local shop with the equipment to install a Huck BOM rivet...