Originally Posted by r8rs4lf (Post 9424857)

So I went under my truck to check clearance from the frame to the bump stop.

Frame to top of bump stop is about 4 3/8".
Frame to that perch (looks like the first point of contact) where the tape measure is, is <6"

If I do a 5" drop, that would leave me with <2" of travel before the frame comes in contact with that perch taking into consideration there is no sag on this 54yo suspension.

Ideally, how much clearance should there be between both contact points?

Pics are sideways again. :help:

Originally Posted by SCOTI (Post 9424868)

Too many variables for one right answer.

Given years of experience w/these old trucks, I'd say you want/need @ least 3" of travel before making contact. That would likely be fine for ~75% of normal driving situations. Jacked-up roads where you live? You'll def want as much clearance w/o contact as possible.

You reference an image of the rear-end axle tube to the frame rail..... That's not the only clearance issue. Did you measure between the differential & the bed floor? What's that number? With mild drops it's usually not an issue but it's a dimension you should know the answer for when making decisions. I did not measure between the diff and floor. I will get under there and measure though. This is my first go around with this so I appreciate your patience.

The location of measuring matters. You show a measurement from the base where the bumpstop mounts to the bottom of the frame rail but it sure looks like that mounting base is lower than the top of the axle tube. You are correct. So if I remove the bump stop, the frame will hit that "perch" on the other side of the bump stop mount first. In my second post with the measurements I refer to that as a "perch." Not really sure what that is, but it looks like it's part of the bump stop mount that wraps around the axle tube.

I'm also seeing only 3-leafs.... If you purchased 'dropped leafs', how many leafs are in their set-up? According to the CPP site it comes with 4 leafs.

Originally Posted by Sunchild714 (Post 9424889)

I have a 4/6 Western Chassis drop without a c-notch https://westernchassis.com/1965-72-C...-Lowering-Kit/. It's pretty close, but no bottoming out. Challenge has been finding better shocks that work and fit. I settled on a set of CPP shocks all the way around. Not the best ride but it works.

Originally Posted by WHYBYNU (Post 9424894)

I did a 4-6 drop almost 20 years ago without a c-notch I've probably bottomed out 1-2 times at the most on really scrappy roads.

Originally Posted by dagnabbitt (Post 9424927)

You can do 2/4 with springs alone, I have been told. With leafs in rear get some axle blocks. It's a cheap and reversible way to see if you like the ride height without making it complicated, too. From what I understand, the rear end needs to be flipped to use lowering blocks correct?

I've never met anyone who said they went too low and that they regret it. But that is a nice original truck, a mild drop would look great. That's exactly what I'm shooting for.

Originally Posted by WHYBYNU (Post 9424989)

Thanks for the compliment. I guess to be correct 4.5 front drop 2.5 spindles 2" drop springs on the front. In the rear 5" drop springs 1" blocks.When I went to Wilwood disc brakes used same drop springs but had to switch to 2.5" drop modular spindles on the front. Hope that helps..

Originally Posted by r8rs4lf (Post 9424992)

So I assume you started with drums up front?

I have factory disk so I don't think I need the modular spindles. Correct me of I'm wrong.

Originally Posted by SCOTI (Post 9424925)

Coil vs flipped leaf = 2 different scenarios guys. He stated he wants a mild drop & I would not call 4/6 or 5/7 mild. Mild is 2.5/4 or 3/5 max in my book.

Previous trucks I've been involved with did have issues w/making contact @ the frame (no bumpstop; no c-notch builds).

Originally Posted by KQQL IT (Post 9425021)

I thought i read it was a leaf truck..

Originally Posted by Richard (Post 9425194)

Not hard to see the results of an axle flip here as the dimensions are posted.. Drop will equal the axle plus the pad under it. Bump will be against frame. As existing spring specs are not known. Any other options are a guess. The diff would most likely not hit unless frame is notched.