How does the suspension in our old 70s pickups compare with that in a newer truck, for example a 2011 F250 super duty, vs my 1973 F250 Camper Special, (7500 lbs GVWR) and if both truck were 2 wheel drive, regular cab, long box trucks with similar load capacity, what is all that different between the suspension on the two?

The last I heard Ford was still using coil sprung twin I beam on the front, and a straight axle with leaf springs out back. That is the same setup I have on my 73. The question is, what has changed? I've heard the i-beam length changed, the rear axle is now a sterling, vs my dana 60, but other than that, it seems like basicly the same suspension that Ford has used since 1965!

Basically, what I am asking, is a 70s F250 with a similar load capacity as a super duty going to be as stable and handle as good as the new truck?

One final though, the basic vehicle weight of the 2011 is going to be a lot higher than mine, so comparing the GVWR isn't going to be fair. My 73 weighs 4,200 lbs empty, I've read a brand new f250, 2wd can weight over 5,500!! So the 2011's GVWR is going to have to be higher to allow it to carry the same cargo weight.

Sam

 

yes the basic layout of the suspension is the same. Yes mounting points have changed a bit and steering is now front steer, but all in all the principals are the same.

Spring rates have seemed to get a little "lighter" over the years to allow for a more car like ride, but a good set of shocks can do wonders on our old beasts.

So yes the old trucks can be just as steady. As far as handling - I would think they would be somewhat similar, with the newer trucks winning out due to better braking systems and most likely, improved turning radiuses. I wouldn't expect a night and day difference between the 2 though.

 

I do believe the newer trucks do not have the twin I Beam front suspension. IMO, the new trucks do drive, handle better. Some of the additional weight in the new trucks is safety mandates and driver comforts. Boxed frames add weight. Not to mention the new ones are quiet. But I would still rather drive my '73.

 

I would imagine the original bushings of yesteryear may not be of the quality that the modern bushings offer today, but I don't know that for sure. I do know that when you buy replacements for our old trucks, you have the option of higher-quality upgrades.

Also, are sway bars standard now? That may be a big factor in comparing handling old vs. new.

And as mentioned, quality shocks.

 

The twin I-beam was still used just a couple years back on the super duty 2wd F250/350, any higher and they got a straight axle. I don't know about the 2011 models.

The main design changes are:
King pins dropped in favor of ball joints. Better alignment adjustability, but more frequent replacement needed.
Radius arm bushings are drastically different. Let's face it, the '65-97 radius arm bushings were poorly designed, they should have been more like a leaf spring on the frame end. They are now. Not sure if helps lifespan of the bushings, but should improve ride and driveability.
Steering linkage moved to the front side of spindle. This was done back in 1980, so it hardly counts as a "recent" update to the design.

 

Right, that all makes sense. The ABS systems does seem to make a difference on the newer ones, and they definitely are quiet! Other than that, sounds like it's about the same. Good to know! Seems like the only huge advantage the new trucks usually have is stuff hasn't had a chance to wear out yet!

I don't know if swaybars are standard now or not, but my 73 has one in the back, and I'd like to add one up front. Some new suspension bushing would help I'm sure.

Mike, I was reading in your thread about the springs you bought for your 73, they were "progressive rate" or something similar, I'd be interested in seeing how you like them. They would probably make a big difference too.

Eventually I'd like to buy a camper and use my old pickup to haul it around, so if I fix it up it sounds like it should do just fine! I've got some engine work to do first, but after that, upgrading springs, bushings and such is the next big step.


EDIT: I wonder what the cut-off date for twin I beam was? Or maybe they still have it! I'll have to drop by the super duty section and see if I can find out.

I wonder, what is the benefit of front vs rear steering?

Sam

 

recently upgraded my 1970 ford 4wd crewcab. rear leafs are now upgraded to 2009 leafsprings 3/4ton. The major difference is the length and wider than the factory original at about 53" if I remember correctly. My 2009 rears are 66" by design this will ride a little better than original. this is all I hope to gain in this application. The newer dana 60 axles have bigger diameter tubes but thinner. So have to be careful in what you by and your application. They are trimming weight anyway they can.

 

It might be a while before I can tell you, as you can probably tell from the current state of my truck, but I am looking forward to finding out!

 

Well, I was digging around on ford website and found this: 2012 Ford Super Duty | Detailed Chassis Specifications | Ford.com

On there, at the top of the list, it still shows twin I beam as an option! That's 46 years (and counting!) for it! That's incredible! I guess Ford really did have a better idea when they came up with it.

Sam

 

I dont know how much quieter the new ones are... my dads 78 250 that he had was as quiet as a hurst. And compared to a 2009 explorer (newest thing ive driven to compare to) Id take his 78 based on sound alone. WAY more road noise in the newer rig, lots more exhaust resonance, and when you romp on it, sounds like the engine is sittin in you lap.

When i asked a more experience mechanic why they went from rear steer to front steer he claimed it was to allow for more parts to interchange.

As far as rear payloads, my grandparents have a 94, 99, 03 and 11 F-350 SD, all of them with the exception of the 94 squat more than mine when loaded with the same weight (bout 900lbs of salt blocks) mine, the 99 and 11 dont have overloads, the 11 is by far the softest suspension and squatted the most. Dont really see much logic in the design to be honest... it has 3 leaf springs, and imo the 99 and 03 ride better. the 94... haha .. is a tank, and rides like a tractor, but drives the best out of all of em. Mine rides about like the 99 stiffer than the 03 and 11, but far from harsh.

I know these are all F-350 4x4 CCLB (sept mine) but maybe some insight into the suspensions from a comparison angle.