Technical Twin I beams: The good, the bad and the ugly. School me

Thanks all. I'm after a 65ish truck. You've put my mind at ease.

 

We had many on the ranch, over the years, and never had any trouble with any of them.Of course we kept them in good shape and greased them! They are the strongest best riding front ever made! Bar none! Still have some on the ranch….we’re working for a living …not long ago!
You will never see a twin I beam front end setting on the street with a broken ball joint…… like one of the other brands of trucks of the same era!





Bones

 

A mechanic I used to know (RIP) worked for a road construction outfit for a while doing maintenance. They had been buying Ford pickups, but got talked into a 'other' brand by a fleet salesman. Work tickets for front suspension repairs exploded, they didn't keep those very long...

 

Back in the day my dad had a 1973 F150 that had a shimmy issue and I had a 1978 F150 which didn't shimmy but wore the outsides of the tires pretty quickly. Both benefitted from an alignment at a shop which specialized in trucks. Dad's shimmy disappeared and my tires wore evenly from that point on. I can't speak for my dad but I could peg+ the speedometer and it was totally stable. Both suspensions were factory spec--not lifted or dropped.

 

In the 60s the local Chevy dealer decided to do a front end alignment pre delivery on new cars as the alignment was not to spec. The cars that got alignment came back at about 5000 miles with tire wear. They figured that new springs settled enough to change ride height and change alignment Swing axles are bad about camber change. And your local alignment shop don't have the tools to change solid axle camber. Most Ford dealers would only set toe.

 

The early Twin I Beams had king pins. At some point, Ford switched to ball joints on the Twin I Beams. My $1,000 Craigslist 1986 F150 has ball joints. 37 states of driving later - it still has the same ball joints.

Over the years, the truck got modified (15" front tires, 16" rear tires, 4 cylinder diesel, 5 speed manual transmission). The original ball joints are still there (and still tight). The rubber in the pivot joints got very tired and the radius arm bushings got very worn out (loose). I (temporarily) shimmed the radius arm bushings tighter with oversize washers (and re-set the toe-in).

Eventually, the worn out radius arm bushings cause twitchy handling - especially noticeable when braking hard. Last year, I finally sucked it up and replaced the radius arm bushings (got the adjustable type for 2 degrees more caster) and pivot bushings. An "interesting" task for a 76 year old. Both the Chiltons and Haynes manuals call for disassembling the radius arm from the strut rod (my Harbor Freight "Earthquake" impact wrench has trouble with that big bolt (and the nut is nearly inaccessible as it is buried inside the coil spring).

The desert rat procedure involved 2 floor jacks and a ratchet strap. Safety gear is mandatory, curse words and throwing tools is optional....
1. Jack stand the truck and remove wheels, and brake calipers
2. Loosely support I-beam at both ends with floor jacks
3. Remove I-beam pivot bolt (Cummins oil pan in the way, used "death wheel" )
4. Lower both floor jacks a "little"
5. Unbolt spring (A clip at the upper end) from the shock tower
6. Remove the nut from the end of the radius arm
7. Use ratchet strap to pull the radius arm out of its socket
8. Carry the entire assembly (I-beam, radius arm, spring and brake/spindle assembly) out of the way
9. Replace pivot bushing (carefully note that the bushing shell has a tapered end - installing it with the non tapered end first is difficult <sigh>
10. Installation is the reverse of the above procedure (use new radius arm bushings)

Russ

 

The early 1 ton Twin I Beam trucks did eat tires. My neighbor ran a construction company specializing in gas station building and maintenance. He, and his dad before him always ran a large fleet of Ford 1 ton utility bed trucks. After about 2 years of running Twin I beam trucks, they calculated that the increased cost of tire replacement would buy a new 1 ton truck every year. They replaced the entire fleet with non-Ford trucks (I don't remember which brand they settled on...).

I bought the last straight axle truck from his fleet - 1964 F350 with a utility bed and a hydraulic tail gate lift. Had the baby small block (221 CID???). Never did anything with it, as I soon moved to Arizona.

 

Never a problem with our old '65. HRP

 

Around 1946 to 1950 Allard got pretty good results with real short "twin I-beams."

https://www.tildentechnologies.com/Allard/index.html

https://images.squarespace-cdn.com/...MNEGR3F531Y/Allard_J2-1513_15.jpg?format=750w

https://images.squarespace-cdn.com/...2KIKUCWLQU/Allard_J2-1515_03.jpg?format=1000w

 

I have the brand of dropped beam pictured with the hammertone finish. I bought 'em in August, and apparently they have added reinforcing plates to that particular area. Mine have those reinforcements.
But I can guaran-dang-tee ya, I will be inspecting them often!

 

I've had a couple. To me they are what they are, a truck front end that's cheap to manufacture.

Sensitive to camber change just by adding or removing weight to the bed. Want to see camber change quickly? Throw a trailer on it.

For average driver they're fine, but for anybody like farmers then they can be a nuisance, loading and unloading hay bails, throwing stock trailers on the back then all bets are off when it comes to trying to align one and getting it to wear tires properly.

Thru the years of working on them in the shop, we have done everything to make them handle better, sway bars, stabilizers, heavy shocks, dual shocks, urethane bushings (which I hate on them). But I still prefer independent upper and lower controls arms, handle better, better tire wear and better ride.

If I'm going to use it as a heavy use work truck then just give me a solid axle and save alot of trouble.

 

There was a '56 Ford PU built down here years ago by a local hot-rod magazine, a 65 twin I-beam was retrofitted along with a brake upgrade. I recall that the reviews were favorable at the time. In saying that, Ozzie engineering requirements are more stringent, the modifications were done correctly and not by a shade-tree weekend builder.

 

We’ve been working an old f350 dump for the past 25 years
Scrap, gravel, garbage and trailer pulling duties.
No tire wear issues at all
Grandpaw has a 3/4 ton for camping. A slide in then a bumper pull. No issues with tires.
It if you have plans on super low, the chassis are 34 inches wide. The same as a gm behind the xmember.
Just saying

 

On the ranch we have a 1974 one ton long wheel base flat bed that I put a 428 Corba Jet in to pull cattle trailers! It is still on the ranch, altough we don’t use it much any more! It was used to haul cattle in a 28 foot stock trailer that weighed 6000# pounds empty, various weights loaded, 100 miles each way, many times each year, since 1974. It has a twin I-beam suspension that was maintained and never gave any trouble! This truck had many other jobs on the ranch as did many other Ford twin I beam trucks, never had any problems with any of them! Some you folks must be doing something wrong….or I’m just the luckiest guy in the world for the past 60 years! Not! Lol










Bones

 

You’ve spent too many years in the sun.

No 221 ever in a Ford pickup, not even a Ranchero.

The only v8 in a 64 F350 was a Y block 292, and that was gone the next year, replaced by an FE 352.

 

I've had two '65s and a '76. All of them rode great, handled better than I expect an old truck too, and never had any problems with tire wear. And when the frame rusted in half on the '76 I took the front beams and power steering box out of it and put them in the second '65 to get power discs and power steering.

 

The twin I beam, like a lot of trucks, has a wider track width in front than rear.
Ford didn’t correct that until 73ish.
I have a stock wheel in front with a wider reversed wheel in back.
Looks cooler than the same offset/width all around. (My worthless opinion anyway)

 

Did my 68 that way! Ten inch wide wheels in back , seven inch in front! It is still sitting on the ranch with those wheels on it!





Bones

 

A Google search confirms the Y block. BUT, it was too many years on the MA/NH border (brain-freeze).

That was about 1978 - It was a tow it out of the field deal - All I ever did to that truck was put a working battery in it and file the burned points. It never did get registered. Maybe my memory is faulty (a 7.5 hour open heart surgery has played some "tricks" with my memory), or maybe the shop swapped the small motor in it as an attempt to get better gas mileage.

Russ

 

Ford went to the twin I beam in '65. There was a time when '65 vehicles were only acceptable if they resembles '64 vehicles, '65 seems to be our new cutoff date but even if it weren't the '65 Ford closely resembles the '64.

That said the Pinto suspension did not happen until 1970. Oh sorry MII, well the Pinto happened first. LOL

 

I get a little confused on the 64/65 thing too.
However, zero pre 65 builds had 350/350 combos either.

 

Or 5 and 6 speeds.

I am thinking about seeling the house so I can buy a Coyote and telling everyone its a hemi. LOL

 

Hey the bossman did grant a waver for newer transmissions.
He must like overdrives.

 

I owned a 68 F-250 for 47 years, had 350,000 on the Odometer when I got rid of it....
Had the front end apart twice in that time... once for a total rebuild, king pins and all....
and once to upgrade the brakes to disc and clean/freshen the rest...
The only time I had tire wear problems was before the rebuild....

LynnW