The Stovebolt Site Forums The Shop Area The HiPo Shop IFS vs Straight Axle ???

I'm torn between IFS or straight Axle on my 38.Don't think the total cost would be that different as long as I keep it simple.Both systems require new springs,shocks,steering,disc brakes etc.Does IFS really ride and handle that much better in a light truck like these ?I am adding 283 with a 350
Penny for your thoughts

After driving my 53 3100, originally with straight axle, then after sub framing, I'd vote for IFS! I've only heard good things about IFS, improved ride, handling, and better braking. In the end I say if you got the money, IFS is the way to go. Just my 2cents.

I've never driven an old truck with an IFS conversion, so I can't really compare.
But I am really happy with my upgraded leaf spring setup on my 55.1 1/2 ton. Posie's Dual-flex on the front and teflon sliders between the leaves in the back.

Another off the wall thing to consider is your title. Does it reference the body number, frame number or engine number? An IFS conversion will probably obliterate the frame number.
I have this issue with my 57 1/2 ton project. The VIN plate is missing on the cab, so the frame number is the one on the title. If I were to add IFS I would have to re-title the truck.
According to the Texas DPS guy it talked to, that could turn into a big hassle.
YMMV. But better to know ahead of time whether its a problem than to have an unpleasant surprise.

regards,
Leon

I would rebuild the strait axle. king pins, steering, springs, disc brakes and so on. remember it lasted this long from the days of bad roads and being used as a truck, so theres no reason to think it won't work now.

Nothing wrong with a straight axle. Sure it rides like a truck, but it is a truck. I have put a lot of miles on my straight axle trucks and wouldn't think of changing.

I would recommend power disks on front though.

cletis How well does the straight axle handle at freeway speeds ?

I changed my 55 2nd series to independant IFS suspension.One of the best moves I made while building that truck.It also has power R&P steering,which is sure a nice upgrade.It drives and handles like a new late model pickup,and I can run in the fast lane all day long.So I would highly reccomend independat front suspension.

I agree completely!

Grigg

Well....if you are popping a 283 / 350 setup in, that negates the " stock " issue. The IFS setup allows you all sorts of options for suspension drop, springs, power steering, and comes with disc. brakes. Ride is better.....IMHO.

I have a straight axle in my 59 1/2 ton gmc. My 59 has a 1959 pontiac 389 that has been bored and stroked to 447 inches. It also has 3 2bbl carbs and runs like a raped ape. I have 12 inch discs on the factory front end, and a very rare factory power steering setup. I wouldn't change it for anything. Oh yeah, I have already driven this truck 9000 miles this year as it is my daily driver.

I realize not everybody can have the factory power steering that i have. But I think some changes alter the truck's character too much. If I wanted something that drives like a car, I would get a car. I like the way my truck squeeks, rattles, and wanders down the road. It's all part of the fun of driving an old truck.

It handles great at 75-80. It tracks true, no fighting to keep it in it's lane. I have taken several long trips in it including twice to PHX and back and 3 times to KC and back.

There's alot of Gassers out there that have a straight axle, and they go fast!!!!

My '37 still has the straight axle, and normal highway speeds for me are 65 to 70 mph. I do keep a close eye on whats going on around me, a sudden move is not going to be like a modern truck! I doubt IFS would change that fact, these trucks are just to high centered for real evasive maneuvers.

Mine does ride like a truck, a nice truck, but still a truck.

Joe

That's so strange.
The manufacturers have been trying to make trucks "drive like cars" (good ride quality, low noise, good directional stability) for 100 years. The reverse (stiff ride, high noise, wandering) is also called "bad engineering".
Why didn't they do a better job?
It interfered with their profits.

New king pins, new spring shackles,spring pins plus rebuilt or new road springs make a huge difference to the way an old truck drives. But it will still drive like a truck.

I still have the straight axle in my '50 truck, as well as the repair work, I have fitted a power steering box, disc brakes and a sway bar. The truck rides dead stable at 70+ MPH mile after mile, and you could hold the steering wheel between one finger and thumb if you wanted to.

Stuart.

Stuart, to bad we are so far apart, we could travel together. Mine drives the same way, dead straight and one handed!

Joe

Wow thanks for all the response, I have been checking out various IFS and some sound sweet but big bucks. I have a 71 GMC that could use but by the time you correct for the wide track withe and extra height I don't think its worth it. I'm leaning towards the straight axle with PS & Pb.

Ford and Dodge still put beam axles in the fronts of their 3/4 and 1-ton trucks.

Another vote for sticking with the stock axle. Give it solid rebuild, set of quality shocks, and maybe a sway bar, it'll handle and ride just fine. I kept the beam under mine, it handles and rides just as well as any full size truck I've ever driven. Tracks just fine (other than needing the rf brake readjusted) at speed, and I have run it to triple digits with no problems in handling.

Unsprung weight, bump steer and individual wheel camber changes are very small on an imaginary flat, uncrowned road with no surface irregularities.
But then, a pool table doesn't need any suspension at all, just low tire pressure.
As the road gets worse, the difference between 1900 technology and 1930 technology becomes painfully apparent.

Yeah Man,it all depends on what kind of ride and handling you are looking for.If you wanna keep it all original then you will have to put up with what you got. A system that is very outdated.I prefer to update the old vehicles and make them ride and handle more like todays vehicles.A lot of others here think that the original suspension is just as good as the IFS systems available today.In my opinion ,if that is true why did the truck manufacturers change over to the modern IFS suspension aystems on their newer trucks.My daily driver is a 2009 GMC Sierra pickup,that rides and handles pretty darn nice.It was not my first choice when buying a new pickup,but it has worked out pretty darn good.My first choice was a new Toyota pickup,but the price was just too high,to swing a deal.The GMC worked out on price alone.So in all fairness it is your truck and fix it up however it makes you happy.

"...if that is true why did the truck manufacturers change over to the modern IFS suspension aystems on their newer trucks."

Could it be so they'd ride like a car so they could sell more trucks to people who don't like the way old trucks rode?

It'll stick with my I-beams, there is absolutly nothing wrong with a truck being a truck. New trucks with real axles ride quite well actually, and old ones are just fine.

We dont have those in Illinois, in fact, we have some of the worst roads in the country. I've driven about any passenger vehicle one can think of on them, and i still would not change out my rugged, proven beam axle for most of what passes for a "truck" ifs conversion that's on the market.
BTW, I do suspension and alignment work for a living as an ASE Certified Master Mechanic.

Here's my penny, you can pour as much money into these trucks as you've got and then beg, borrow or steal some more and it's still not finished. If you're going to ruin it with an automatic go ahead and throw in that IFS.

FWIW, daily driver only vehicle the last 13 years, 55k miles, stock axles, daily driver year round only vehicle.