The Stovebolt Site Forums The Shop Area Driveline Original front suspension vs. IFS

I've been reading some of the latest posts concerning the original front suspension. I've not removed mine yet on my '50 3100. My determining factor has to do more with cost than driveability. I know all the spring bushings will need replaced. I would also want to install 5 stud dropped disc brake spindles. In addition, I would have to find a proper steering box with power steering compatibility. I assume some if not all linkage would need to be repaired or replaced. There may be additional items I didn't list and as always the unforeseen parts that add up quickly. An IFS from Speedway will cost $600 for the bolt-on crossmember and approximately $1,400 for the rest of it if my memory serves me correct.
Do any of you want to weigh in on the comparative cost issue? Time I have, funds not so much!

I’m following this as well as I’m in the cross roads myself. Did you price out how much it would cost to rebuild the original front suspension? The way I look at it is that big trucks still use the I beam and leaf spring technology still, so how bad can it be?

If all the parts are good and you keep it greased the original front axle will be fine. Now, it is not going to drive like a new vehicle would, but your driving an old truck.
Go through it and change what needs to be changed and drive it, you will get used to it. Then if you don't like it change it. to what ever you want, it's your truck.

My '37 has everything new on the front end, springs, shocks ( tube type ), king pins, tie-rods, etc....... It drives as good as my '03 Toyota, I have to work a little to park at very slow speeds, but's still no problem. Your truck will drive pretty easy once rebuilt, especially if you get the steering box adjusted and lubricated. Mine has disk brakes on stock spindles, it might not have that if I could have figured a way to but drum brakes with matching bolt pattern to the rear. You won't need disk if the originals are right. The original setup has lasted 70 years, you think the modern add-ons will?

I honestly love how my 3/4 ton drives. Its a little bumpy on backroads but it’s mostly from the rear not the front. I put like 700lbs worth of wood pellets in the back before and it was amazing how nice it rode. Yup its a 1949 truck so no it dosent drive like a new truck. If you want a new truck they make new ones everyday.

If it is a matter of Dollars then do the math. A drop axle will run you about $400.00 ( I bought mine from Sids) I haven't seen drop spindles for these trucks, the disc brake kit can be be had for under $300.00, the power steering conversion kit about$150.00 ( you will need to locate a used steering gear to keep your costs down. Of course you would still need to freshin up your spring set and shackles. If you handle all of the labor involved yourself It can be done relatively cheap. As Tommy said though you are driving a truck.

Maybe you should post this in the HiPo forum

If you go Independent front suspension, you will have a weaker front end with no load carrying capacity. You will also need to change the rear axle so you can have matching bolt patterns on your wheels, so add in driveline , steering column, brake booster & master cylinder, tires & wheels, welding labor, and a whole bunch of small misc. stuff.

Rebuilding what you already have will be cheaper. Tie-rods and king pins are not that much money, and it's something you can do with not many tools. Springs can be pulled apart and cleaned for the price of a couple center bolts. Changing out the spring bushings is also a DIY project, there's a thread about it going right now in this forum. Rebuilding the steering box requires a couple gaskets and a couple bushings, there's even a online manual to walk you through it. Once that's done, the whole front is like new. Drive it for while and see if it really needs changed, if you are not happy, sell off the rebuilt parts and buy what you want, someone is always looking for original pieces.

Joe H's post (and Cozum's and Tommy's) should be placed in the Hall of Fame.

Some members have good and safe IFS conversions.

My bet is that there are more failed and/or unsafe conversions.

However, do what you like.

Drop spindles on a straight axle aren't going to happen- - - -there's no room to move the spindle up. Dropping the axle makes the truck a straight line only vehicle- - - -it will handle horribly in any sort of a turn. Bump steer will also be a problem unless you plan to do all your driving on roads as smooth and flat as an airport runway. IFS- - - -putting a sub-compact car suspension under a truck kills the load carrying capacity- - -that's OK if the heaviest thing you're planning to haul is an iced-down Yeti cooler full of beer to a tailgate party. If your game plan is to build a show truck that's going to be trailered most of the time, do whatever your budget will allow to the ride height and suspension. If you plan to actually drive it on the public roads, your safe, affordable options will be somewhat more limited.
Jerry

End the end, this is your truck, do as you want, we just want you to know, original equipment is not as bad as most think it is once it's fixed up.

My '37 truck is close to original, looks like it anyway, but it has aftermarket leaf springs with custom designed spring rates, later model ( '55 ) tie-rods, adjustable draglink, later model ( 1941 ) steering box, and I believe 1955 straight axle. Over all its still as designed, it rides good, drives easy at all speeds, and still uses truck heavy parts. Disk brakes are the only non-original type part on the front.

Joe

You have a couple of really good comments here and I think they'll be obvious to you. If you rebuild your entire front end (including steering box) and leave it at original height, etc you'll have a fine pickup. If you go with IFS, you're entering a money pit, and depending on who does the work you might make irreversible changes that make everything worse. Please remember your truck was designed carefully and thoughtfully by very intelligent people...and the entire thing (especially the frame design) was intended to work as a unit. Keep it stock, adjust caster a bit higher (to help it track straighter), get new radial tires which mimic the original width as much as possible (NOT wide ones) and keep the entire thing greased regularly. Also I'd encourage you to replace your leaf springs. Those wear out, weaken, etc and new ones will make a difference. As for disc brakes, millions upon millions of electrons have been sacrificed here discussing one v the other. Drum brakes are just fine if they're correct and kept in good nick.

I should have mentioned that the first vehicle I got to drive after getting my license was my dad's '54 3100. I remember the pro's and con's to this day. In doing research I recognize that dropped spindles are not available for the standard axle. A dropped axle would now be the route I would take. Additionally, power steering is a must for me. I want ALL the creature comforts.
I have already installed a 10 bolt rear end so the front hubs will have to be changed as well. Obviously, I'm not doing a restoration...more like a ratty restomod if there is such a thing. Nothing of any consequence will be hauled in it...other than what HotRod Lincoln mentioned!
I appreciate all of your comments. As I mentioned in my original post, cost is my biggest concern on what I do upfront keeping in mind of how I want the truck to look. If it's a wash either way, which is my best option. I know it comes down to my preference, however, I want it to be an enlightened one.
I wish some IFS bolters would weigh in.

We did IFS on my son’s 1953 3100 but we went the grafted Camero k-member route. Worked great and drives great. Lots more work than a bolt on.🛠

Find a Nova or Camaro with a lug bolt pattern that matches your rear axle, and graft the entire front frame from about the firewall forward to your stovebolt frame. That way, you can take advantage of the millions of dollars' worth of engineering that made the suspension, steering, and brakes work on the original vehicle, not some shade tree hotrodder's idea of what works when a sub-compact car crossmember gets grafted into place.
Jerry

Whoa now!
You want ALL the creature comforts but you have caviar tastes on a hamburger budget. Not possible. Here is a 53 GMC on a shortened and narrowed 74 Caddy chassis that fits your bill. 500ci V8, p/s, pb, a/t, a/c, power seat, cruise control, power windows, remote controlled everything, etc. Rides and drives like a Cadillac and all yours for a mere 53k. I think you need to choose ONE and forget the other. Truck 25 years old when pic taken.

[img]https://i.postimg.cc/5jZW3MYG/51-GMC.jpg[/img]

[img]https://i.postimg.cc/WttJZ0g8/51-GMC-009.jpg[/img]

[img]https://i.postimg.cc/Wd43Rv8n/51-GMC-007.jpg[/img]

[img]https://i.postimg.cc/s1p9xYrL/51-GMC-008.jpg[/img]

Nice.

Ed

coilover...creature comforts as in PS, PB and especially AC. My wife won't ride along in the summer without AC. Come to think about it that wouldn't be all bad! Scratch the AC!!

So whats the Problem?

Personally I just couldn’t put a Mustang front end on my Chevy truck.

Check out the chain drive steering in the last pic

Can't help but wonder how the steering wheel feels on an interstate clover leaf exit when the cab rolls on the rear shackle mounts while the steering box up front does not.

Let's see now, the GMC/Cad combo was used by a plumbing contractor with 61 crews to carry blueprints and consult with foreman on a daily or weekly basis. It wore out the original 472 engine which was then rebuilt and wore out again. The present 500ci engine has around 100k miles on it so the total has to be close to 400k miles and the chain steering has required ZERO attention in that time. As far as cab to frame flex the chain is way more forgiving than the rigid steering tube/shaft solid at the frame plus solid to the dash and brace rods. If you have a lathe like our big old 1941 Monarch just anchor one end of a 3/4" steering shaft and use two sprockets with chain to the head stock. Leave the tail stock loose on the ways and put the lathe in low gear. It will wind the steering shaft up like a pretzel and unwind it back again as many times as it take to destroy the shaft and the chain will be unfazed. Believe it or not we didn't just fall off the turnip wagon with just a hammer and pliers to work with. Now it's all computer design but in the beginning we built them starting from chalk marks on the floor so frames, suspension, steering, roll centers, CG, Ackerman, anti dive, etc are familiar to us.

Here's my 2 pennies worth. As far as the solid axle goes, you're not ever going to be able to duplicate the strength and durability of it. On a 60+ year old truck, you're probably going to have to replace the spring bushings and shackles. Not a huge deal. When it comes to kingpin bushings, as long as everything feels tight, you're probably ok. If you have to replace them, it's possible that you're opening up a can of worms. As far as power steering goes, I haven't really seen a kit out there for the solid axle, that I really like. The Toyota steering box setup is probably the best, but it's pricey and again, you're opening up a can of worms. There are vendors out there with front lowering leaf springs, of course this opens up a can of issues with pitman arm angles, etc... If you're looking for something stock, there are also vendors out there with OEM style leaf springs.

As far as IFS goes, the kits that are on the market now are plenty strong, not to mention there's a ton of aftermarket parts and options for them. The last car show I went to there was a couple dozen vintage trucks. Only 2 of them had the original beam axle, the rest were IFS suspensions, so there's plenty of folks out there that trust IFS on vintage trucks.

I know you mentioned the bolt on kit. I'm not familiar with it, but I know the Speedway kit looks identical to the old Chassis Engineering setup, which is now owned by Heidts. From everything I understand, it's a quality product.

On my 54, I was originally going to stick with the solid axle. Well, I changed my mind on what I wanted (about dozen times). I picked up a crossmember kit from CPP, it was only 200 bucks. I don't want a truck that's dropped to the ground, so I added a little material to the crossmember and trimmed the spring hats accordingly. I'm trying to be economical and I bought control arms and spindles from another vendor. In hind sight, I wish I would have bought the whole works from one place.

With an IFS setup, there's going to be no inexpensive way around it. Most folks doing an IFS are doing a complete drivetrain swap already, which I believe you're doing also. My advise is to call around and talk to some vendors and decide what's best for you. Most vendors can build a custom kit based on what you're looking for. I see you're in Iowa, maybe take a trip to Cedar Rapids and see the folks at Street Rod Engineering or even take a day trip to Wisconsin and talk to the folks at JW Rod Garage. Heck, they might even install the kit for you at a reasonable price.

I would second that on buying a whole kit from one vender. No matter if it's brakes, gauges, interior, and suspension. If something doesn't fit, you need to make one phone call, not two three trying to get them all on board with each other.