stretching a truck frame...

As soon as I get home I'll look for it. I may be wrong, so don't trust me on this; But I think if the pinion angle on the rears matches the inclination of the engine/trans, you will be OK, as long as the vertical distance between the u-joints is within a certain range.

 

Try this link;

http://www.thedieselgarage.com/forums/showthread.php?t=113392
You can Google "driveline angle calculation" & get a bunch more as well.

 

Rank, I just ran with a Landstar driver that had his 1998 Pete streached out. He had it done in Birmingham, AL (forgot the name but it's got "frame" in the name of it.... anyways, he streched it out to 305" and he said they put new rails on the back and moved everything (suspension, lines, wiring) all for $2,800 out the door. Worth looking into i think if you're serious. And for that price, I might be having a 315" StarCar here in a few months

 

FWIW,,,most think youd cut the frame between the cab & axles, then add frame to the length you want. This is very WRONG for many reasons. Frames have to flex, & the only way to join them over a spance like that is with a "fish-plate". This stiffens the frame ahead/behind the plate. This is where it will crack, & now you have 8 of these spots. (2 per plate on each side X 2 plates each side)

Do NOT cut the OEM frame! The factory drilled/punched holes for the suspension hangers are exactly the same pattern front & rear. Meaning that you can remove all the hanger bolts and roll both axles out from under the frame outa the way. Add frame to the end of the OEM frame, & re-bolt the front axle hangers, into the OEM holes that used to have the rear axle hangers bolted to. NOW,,,there is just 2 splices (1 per side) & ya don't have to "fish-plate" them because your splice should/will be at the the X-member between the axles where you added the rail. Add frame AT the X-member that goes under the 5th. wheel. Drill the new rail (alignment is good because you used the OEM frame holes, for the front axle hangers that are now bolted to the rear hanger holes. Drill the new rail (a "mag-drill" & good reems will save you hours of drilling) This is all provided that you are a really good welder with the right equipment.

Yes you will have to add driveline which means shaft, yokes, carrier bearing etc. Pinion angle will be adjusted with shims at the carrier bearing mounting bracket up/down. (cheap magnetic angle finder will do it, just measure the angle to the front diff. 1st so ya know what it is, then shim the carrier to match that angle on the new shaft.

What I've told you and others above have suggested, is that unless you really know what yer doin' get someone that does, to do it for you. You can not succesfuly do this with a 225 Lincoln ac buzz-box, or a small mig machine! Want my qualifications? send me a pm & I'll give them to you. Hope this helps!

 

send it to a shop. metal has to be welded a certain way to keep its strenght in addtion certain welding technics for different pressure points ect.....you have to know what kind of steel your frame is what temp the steel needs to be for the strongest weld. welding hot is not the fix either. that just spiders the steel and makes it weaker. you have to weld at the correct temp for the thickness of the steel the type of steel. also a hot weld can warp the steel. even if its just a small fraction when you go down to the rearends it could be as much a 2 inches out which now you will never keep tires on it long. best bet is to send it to a professional shop who has the equipment to keep it straight and knows how to properly weld it.

I am not one for sending things to the shop either. I normal tell everyone do it your self and will be the first to try and explain it out. but this is just one of those things. this is worse than rebuilding your motor. there is no room for mistakes. a bad weld you break the frame a wrong angle you could twist the frame more plus you will be eating up tires like a kid with candy. their is to much at risk for this to be a diy job....good luck though

 

Does anyone know of a good shop in NC that does frame stretching? I have a Columbia with a 229" WB that I wanna stretch to either 255" or 265".

 

good to know about pricing, yes i know the thread is well over a year old. yes i know im dragging it from the dead.

 

Not sure if this has been covered, but! If your not 110% you can do this! font try! I seen guys with trucks they tried stretching themselves, better to find a shop that does these things

 

195" web is a lot already but if you do that your self you could risk tearing of your back axles and messing your truck up