I want to lower the front of my 51' 3100. I noticed the leafs are on top of the axle. Might i put the leafs under the axle to achieve some drop? Just throwing my eyeballs at it, seems to be doable with a dropped steering arm.
i have searched this forum, and couldnt find any mention of it.
"Commonly quoted life advice I dont even try to live by." -Famous Person
Talk to Sid Drapal at Nostalgia Sid's Dropped Axles, https://droppedaxles.com/ He knows what he's doing, and can get you pointed in the right direction. I don't know what all exact reasons putting the axle over the springs is a bad idea, but if it was a good way to do it, it would be commonly done. I can only guess that the handling is questionable at best, and the size of the axle on top of the springs would limit suspension travel.
My truck has had a 3" axle done by Sid that was installed in 2016. With the proper caster and toe settings, and fresh tie rod and drag link with modern tie rod ends, it tracks beautifully and has ZERO bump steer. Highway speeds and two fingers on the wheel.
Would you be making a special saddle for the springs? If I remember correctly, the spring saddle is integral to the I beam axle and is on top of the axle.
Would you be making a special saddle for the springs? If I remember correctly, the spring saddle is integral to the I beam axle and is on top of the axle.
Yes. I have a cnc plasmacutter. I'll be making lots of things i imagine.
"Commonly quoted life advice I dont even try to live by." -Famous Person
You would need to weld the new plates to the axle, braking will apply a lot of rotational force on them due to the extended leverage. Do you even have the room between the springs and frame rails? Be sure to allow for lots of caster angle when mounting the plates.
You might want to talk to a professional spring shop and consider having "mono-leaf" springs made (front and rear) for you. This as the name implies would mean you only have 1 leaf in each spring but that spring would be made to handle the weight and force factors of the AD truck. They mount just like the original springs but the axle sits lower. It has been done before...by several and there are some out there for sale but as I recall only for the front end and they're very costly. Patrick Dykes (of the now-gone Patrick's) in Arizona had these made and was selling them but he's gone now. I drove his pickup after he installed them and it handled and drove just fine. Lowered it by about 2 maybe 2.5 inches and there was a measurable weight reduction. If you only lower the front end you change some things...caster angle being the most important of those things. And if you just remove a bunch of spring leaves from the original AD springs you risk causing those to break...you can remove some leaves and be ok but you won't ever be able to run the AD springs as a mono-leaf spring safely. One thing we discovered with Patrick's springs was that the drag link finally sat parallel to the ground...which is the best situation if you're looking to reduce bump steer. If you have new springs or springs in good nick, your drag link will angle from front to rear upwards about 8 or so degrees. The higher up on the arc you get, the less of a bump it takes to cause your front end to want to change direction...you can see that in my drawing attached. Good luck!
Last edited by Jon G; 07/22/20233:10 PM.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
Years ago when I was younger and dumber i tried just what your thinking. I welded new perch plates to the I beam and moved the axel above the springs, this was on my '59 31. Once I mounted the axel that's where the problems started, nothing lined up, the steering geometry was way off and there was ZERO clearance. I quickly abandoned the idea and called Sid. I now have a 4' drop axel and still had a few issues but nothing like before. In hind sight I would have opted for a 3 " dropped axel if I had to do it again, 4' is just too close on the scrub line.
Last edited by TUTS 59; 07/25/20232:12 PM.
~ Craig 1958 Viking 4400 "The Book of Thor" Read the story in the DITY 1960 Chevrolet C10 "A Family Heirloom" Follow the story in the DITY Gallery '59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting)
If you don't like driving yourTruck, you won't drive yourTruck..| Living life in the SLOW lane
Years ago when I was younger and dumber i tried just what your thinking. I welded new perch plates to the I beam and moved the axel above the springs, this was on my '59 31. Once I mounted the axel that's where the problems started, nothing lined up, the steering geometry was way off and there was ZERO clearance. I quickly abandoned the idea and called Sid. I now have a 4' drop axel and still had a few issues but nothing like before. In hind sight I would have opted for a 3 " dropped axel if I had to do it again, 4' is just too close on the scrub line.
Thanks. Speaking of scrubline. Assuming a bone stock 1951ish 3100, with stock wheels and tires, would a 3" drop axle exceed the scrubline? I did the math on my vehicle with 15" rims, and its a no go.
"Commonly quoted life advice I dont even try to live by." -Famous Person
Sid's web page has some great information on it, there is a layout of how to correctly measure your scrub line.
~ Craig 1958 Viking 4400 "The Book of Thor" Read the story in the DITY 1960 Chevrolet C10 "A Family Heirloom" Follow the story in the DITY Gallery '59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting)
If you don't like driving yourTruck, you won't drive yourTruck..| Living life in the SLOW lane
Just put a Mustang suspension on. I put an AMC pacer on before the Mustang became popular. I have been using it for somewhere around 20 years. I did have an issue with the cylinder which was a flaw in the system and replaced 2 back to back. The cylinders was replaced under warranty.
Ron, The Computer Greek I love therefore I am. 1954 3100 Chevy truck In the Gallery 2017 Buick Encore See more pix 1960 MGA Roadster Sold 7/18/2017
I'm going with a 4" drop custom width axle from Pete and Jakes and Superbell. Designed to leave the ground and safely return to earth. Roller bearing king pins. Custom spindles that are early Ford with Heidts spindle pins (done by me). I'm running a 12.88" rotor that requires at least a 17" rim. IMHO an AD without a straight axle is like a warm beer. It's still a beer but not quite right. Properly set up with the right springs and bushings and a good sway bar there is nothing wrong with a straight axle. That spring has no idea if it's straight or coiled. The magic is in the shocks.
Just put a Mustang suspension on. I put an AMC pacer on before the Mustang became popular. I have been using it for somewhere around 20 years. I did have an issue with the cylinder which was a flaw in the system and replaced 2 back to back. The cylinders was replaced under warranty.
I am putting a mustang ii in the chassis im building. But wanted to 'easy drop' the truck while im driving it around delivering sweetcorn.
"Commonly quoted life advice I dont even try to live by." -Famous Person
I'm going with a 4" drop custom width axle from Pete and Jakes and Superbell. Designed to leave the ground and safely return to earth. Roller bearing king pins. Custom spindles that are early Ford with Heidts spindle pins (done by me). I'm running a 12.88" rotor that requires at least a 17" rim. IMHO an AD without a straight axle is like a warm beer. It's still a beer but not quite right. Properly set up with the right springs and bushings and a good sway bar there is nothing wrong with a straight axle. That spring has no idea if it's straight or coiled. The magic is in the shocks.
Alot of good people drank warm beer.
"Commonly quoted life advice I dont even try to live by." -Famous Person