id like to step up to the taller frame that many of you talk about being stronger...i have a 92 w250 regular cab what will interchange with this...will a w350 regular cab frame work?..or am i stuck with the small frame ..thanks for the tips...

 

you may want to look at the frame you have... You most likely already have a tall 8" frame... It is the 1989-1991.0 trucks that were slighted with the small 6" frame...

Here is what Terry/Mysteryman said:

"The frames from 72 threw 93 are basically the same at a glance but quite different if you look closely..

The 8" (some were 7.5") frame was used on all the cab/chassis models. It was also used on all the 1 ton pickups and select 3/4 ton trucks..

Most of the 3/4 ton and all of the half ton's used the smaller 6" center frame.

The 1st gen diesels 89,90,91.0 250, 3/4 ton used used the 6" frame but it was a bit heavier than the earlier gas version. You could order the 8" frame
if desired but most were called single wheel 350's rather than 250's

89,90,91.0 350, 1 tons used the taller 7.5 " to 8" frame. The 8" was a bit heavier than the earlier gas version..

In 91.5 the 8" frame was updated and is heavier than all the rest that came before it... This is hard to see with the naked eye. But quite obvious on the blueprints. It was updated and the 6" frame was discontinued due to breakage problems... in conclusion.....
All 91.5, 92 and 93's 250's and 350 diesels used the SAME frame ...

The exceptions.....2wd verses 4wd....The frames are the same except for the front cross member's and spring hangers....

Converting a 2wd frame to a 4wd frame is rather easy assuming that you have the 4wd engine cross member and 4 spring hangers...


Converting a 4wd frame to a 2wd frame is a whole lot of work !!!!! You have
to change the front cross member and the engine cross member.. Weld in the motor mounts. Mount the upper control arm brackets.... None of the holes will be pre drilled for you. You will have to drill them all yourself.. The tolerance for these holes is .125 (1/8") on center .. If you miss the mark you may never get it to take a front end alignment or track properly...
I would not recommend doing a 4wd to 2wd frame conversion to a novice
or back yard mechanic..

One last note..... If you need to replace an 89,90 or 91.0 6" 250 diesel frame. And if you can not locate a diesel frame.. You can use an early 7.5" 300 gas frame.. All the holes will line up for the most part...

Be sure to measure the wheelbase of the doner frame you buy...
Trucks that were sold as "cab/chassis" have longer frames than Pickup trucks.

And dually rear axles out of "cab/chassis" trucks are NARROWER than the dually rears out of pickup trucks..

Dually rears out of "cab/chassis" CAN be used in most cases in single wheel pickup trucks.. You may need to change the gears to get highway speeds with the diesel.. 3.55 to 1 ratio is the best choice for all around use when using stock size tires.

I hope this answers all the frame questions"

 

if you are pulling the body and everything just box it. find another 6 inch frame, pull the stuff in the way, and slide it in like a yota. stronger than a single 8 inch. I plan on boxing certain areas of mine, and then building a section that channels over the outside much like mid 90's chebby 3500hd cab chassis.

 

Any pictures of the box job?

 

Be carefull with your frame boxing, I have seen a couple frames develope cracks where the boxed portion meets the non boxed portion. You are strengthening one section of frame which causes the non boxed part to receive more of the stress. Best to box all or nothing. IMO

 

I wouldn't worry about boxing the frame I used my 85 crewcab frame on my first swap and even after rolling the truck we replaced the body work due to frame was fine and it was a longbed so it's a pretty long frame to begin with

 

Mcmopar, I haven't done this, It is just one more project in my head, along the lines of building a house and getting a cumming powered ramcharger. MrExtreme, good points. I was thinking more along the lines of how the2nd gen 1 tons are done, but, again, good point, why not just do the whole thing.