The Stovebolt Site Forums The Shop Area Engine Shop IFS Swaps that are on the road?

OldSub,

I did make templates from the 78 donor truck that located the idler arm and steering box. I did not however measure the angle of the upper or lower A-arm cross shafts relative to the horizontal of the frame. Eyeballing the 78, it looked like the part of the frame that the crossmember bolted to was horizontal, so I just bolted it to the bottom of the 53 frame. I have seen another AD truck with this conversion done that put a big notch in the frame to simulate the kick-up in the newer truck frame, and enable the truck's front end to sit lower. I took the dropped spindles and drop springs approach to lower the front, but may end up installing air bags if I can find a setup cheap enough.

Does anyone out there have this conversion done and on the road? I'm currently updating my article and would like to include photos of others who have done this conversion with a small bio and contact info.

Thanks,
Steve Andereggen Jr.

I've always thought this swap was a good idea. Especially for the 3/4 ton and up trucks. Wouldn't the best approach for installing one of these be to make a jig on the original donor truck maybe right on top of the frame rail (behind the kickup), and have points for the control arm shafts, steering box, and all of the suspension components? Then when you go to install it on the AD truck, you could narrow the jig straight down the middle, and even notch out your frame or the crossmember to lower it a little bit. I've never attempted this before, but I liked how people were using jigs for the subframes and thought this would make it easy.

I struggle with the whole concept of narrowing the crossmember. Doing so changes the suspension geometry. Maybe not enough to matter, but I worry about the implications anyway.

Otherwise, I'd agree, using a jig would be the best way to keep things aligned.

Steve Jr, the guy named in my signature line has one of these trucks with the IFS conversion, and I have pictures of it.

IFS GMC Photos Start down about eight shots. There are a bunch and you'll want broadband before you try to open them.

I'll swap you permission to use my photos for permission to post your new article on my web site.

I am eager to see the new version!

I am trying to contact the guy with this truck. I've seen it at two different ATHS shows about 100 miles apart, and actually passed it running down the freeway on the way to one of those shows. I was in my big block powered 1-ton and hurrying so I didn't spend much time admiring it on the road. It wasn't until later I discovered it was Cummins powered and had an IFS under the front.

Holy Huge Photos Batman. We spots a mid 90's Cummins B. Suspension pics start at photo 14.

Even with Fiber Optic Broad band the pics load slow Steve. I think we are taxing your server.

Server? You mean that five-year-old Dell laptop in my basement? At least it's an upgrade from the 10 year-old Toshiba it recently replaced...

Server Running: 36 days 21:40 hours:minutes
Users: 0
Load Average 1 minute: 0.06
Load Average 5 minutes: 0.03
Load Average 15 minutes: 0.01

Based on this I suspect you are taxing my home bandwidth more than my hardware.

After some Internet sluething and then simply calling numbers until I found him, I managed to find the guy who owns the 1-ton I've seen on the road running an IFS.

Today I spent almost three hours chatting with him about the swap, asking questions and hearing stories. He is a retired guy who has run the truck all over the US. It is an '85 3/4-ton IFS and when I'm not sitting in a hotel room I'll post some pictures and describe how he did it and what he thinks made it a success.

Last Friday I got to visit with Joe at his place out in the sticks between Roy and Eatonville Washington. Joe is an older guy who winters in Arizona and about every second year drives to Maine where he visits his sister.

His travels were one of the reasons I had so much trouble finding him. But the interesting thing is he drives his 1950 GMC with a Cummins Diesel and IFS swap when he makes these trips.

I started this thread looking for someone who had made the conversion and was driving the truck. Joe is the guy. He said he has driven it 90,000 miles since building it 11 years ago.

Joe and his GMC.

So the question is how did Joe do it. He emphasized that he had the front sheet metal off when he did the work, though I didn't get the sense that was critical. This is the only construction picture of the IFS he had.

IFS Construction Picture.

Joe is 76 years old and was talking about work he did 11 years ago. I felt he recalled details better than I do of things I did 1 year ago. He made spacers 11/16ths thick to fit the IFS to the GMC frame. He also put angle iron at the bottom of the frame to make sure it was stiff enough.

The same approach was used for the steering box, idler arm and sway bar. He said before he removed the parts from the donor truck he carefully measured everything and made notes to be sure it would be mounted in exactly the same relationships.

I wasn't clear if he was describing this project or giving advice how I should do it, but he suggested painting the floor, and using a plumb bob and sharp punch, mark the positions on the floor.

My suggestion to him was that I park the donor on a newly painted floor, straighten up and level everything, then set my marks.

Take the donor apart, and then park the new (old) frame over the top, aligning the centerline of the frame and the centerline of the axle with the corresponding marks on the floor.

Then mount the IFS making sure all the relationships are carefully held in place to prevent bump steer or alignment problems.

Joe said if he had it to do again he would narrow the crossmember instead of making spacers. His reason was that the tires stick out beyond the fenders even with custom wheels that brought the tires in more than an inch on each side.

I think that covers the details I collected from Joe. After hearing his story I'm much more inclined to make this swap on my own truck.

My thought today is to widen the fenders rather than narrow the crossmember. I like the idea of keeping the IFS as near its original form as possible. The road trip that took me past Joe's included attending Ron Covell's advanced metal working workshop where I watched him make a fender from scratch. Seeing that I believe I can widen fenders or at least I'm not afraid of trying.

Here are all the pictures I took Friday in their full high res glory.

Detail pics (broadband only!)

Steve,

Since you are not going to narrow the crossmember, you might want to look at the new spindles from CPP. There was an article in either Custom Classic Trucks, or Classic Trucks last month that covered these. They bring each wheel in about 1". They also drop it 2.5" which might not be something you are interested in.

Kevin I checked CPP's web site and it appears the spindles for C-20's all require swapping to five-lug brakes. And while lowering the truck would not be offensive to me, loosing the bigger brakes is not something I'm willing to accept.

I just Saturday attended a Ron Covell (Professor Hammer) Advanced Metal Working workshop where he showed how to make a fender from new flat stock. Based on that I'm feeling brave enough to widen a set of fenders to cover the wider front axle. And that is something I'd enjoy doing!

I've been working with Wayne Osborne, who runs the chevytrucks.org web site, on posting an updated article on the suspension swap. It is up and running and now if you clic on the photos, they enlarge to a bigger photo. I'm in the works on getting more photos posted and have also included links to the other articles on the web. Here is the link to the updated article http://www.chevytrucks.org/tech/63-87_ifs_upgrade/index.htm.
Enjoy,
Steve Andereggen, Jr.

P.S. Steve(OldSub)...How is your project going? What have you decided to do for your suspension? My bed is done and will have the cab and engine out Monday if weather is good. I decided to POR15 the frame instead of powder coating it. It's cheaper and is just as durable. Also, if I decide to put an IFS on down the road I can do so and do a POR15 touch up. I shpuld have the frame done by the end of the month and the engine back in and running, I hope.

Steve your link doesn't work to the website...Joe

Try this:

http://www.chevytrucks.org/tech/63-87_ifs_upgrade/index.htm

Steve, If you can live with the slightly larger wheel well, a big bolt fender is about 2" wider and will bolt in place.

Scott I have some big bolt fenders, both the 4000/6000 type and the larger GMC 450 types. I'd rather keep the smaller wheel opening and the shorter hood of the smaller fenders. I'm really looking forward to the metal work required to widen the fenders, and since I have seveal extra sets I'm not afraid of a little trial and error.

Also Scott, I saw one of your IFS kits on Sunday. I stood in John Henry's shop out in Walla Walla and admired his truck projects.

Steve Jr I have decided to move ahead with the IFS swap. If I ever get my butt out of this chair and go out to the shop I'm going to start the process today.

Hood and fenders are the same length, just wider with a slightly larger wheel opening. You could take the two and get the smaller opening.

My frankentruck is using a 6100 cab and front clip. So I think I will just run steam-rollers for tires unless I decide to spend some $ on the smaller fenders.

[quote=Scott Danforth]Hood and fenders are the same length, just wider with a slightly larger wheel opening. You could take the two and get the smaller opening.-----------------------------------------------------------------------------------------------

If the fender is wider? what happens at the cab? Any definant #s on the + width. I was readdy to give away a good 1ton 88 chasis till I started reading this thread. I'M one of those guys that is pretty hell bent on using what you got laying around. But got alot of Buddys that like to come over and drink my beer and give me that I told you so speach. After the fridge is empty and i tellem I cant restock because I wasted all my time building something that I'm not happy with and should of just bought the allready made stuff.

You guys got some great talk going on. I dont know alot but sure in heck know you can learn alot if just shut up and listen to Guys that "Been there Done That"

My first thought was that I don't want to do that.

But if I'm considering widening the fenders, moving the smaller wheel opening to the bigger fender might be easier. I'm still considering my options for this part.

Today I finished squaring the frame that is the foundation of this project. Its setting on jack stands and I've checked diagonals in a number of places, and have used a laser level to make sure it is not tweaked horizontally.

Maybe tomorrow I'll drag the frame with IFS into the shop and start the actual swap.

Old Sub
You say your wanting to keep this all 1 ton rating. I was sitting at the shop have n a cold one and looked over at a 1 ton I have there a "DUALLY" and notice that the front wheel A "DUALLY" wheel. The offset sets that wheel back in. I bet at least 1-2" INWARD FROM hub. If your donor Chassis width is set for single wheel 8 lug these might give the desired width in front. Just a thought.

But then again my Wife might be Right. Just because I drink alot of "BUD" that does'nt make me any "WISER"

You guys had me worried about all this talk of narrowing the IFS and went back and started measuring what I got and I still think as long as I'm working with 55-59 and 88+ chassis your allright the width is still all the same unless I'M missing something. NOT trying to HYJACK this thread. So I"L Shut the hell up and just come back and check up on your guys progess. Good Luck and keep us all posted.

ExtCab that was one of my early ideas.

I moved away from it for two reasons. First I decided running duals isn't what I want to do. Second, the design of the single wheel hub and brake make it real hard to fit a dually type wheel on it.

Not to hijack my own thread... But I agree your Task Force stuff on a '88 up is a comletely different story.