making a longbed a shortbed

[ROOTNEY88]

rootn good deal on a 69 f250 ranger 2wd ps pb 390 c6, however i have never been a fan of long beds

Would it be hard to throw a short bed on the frame, Im going to lower the rear so moving the spring mounts wouldnt be too hard, I have experiance in welding fab work

I have a 67 short bed doner bed

[MadMaxetc]

Because of the frame bends (up and down) you will have to cut the frame just behind the cab and also some off the ends of the rails.

Other little things like Brake lines and mounting points for the be are easy fab work. They didn't change the number of bolts, just the spacing, thats why you have to move/make the mounts.

[averagef250]

If you already have the bed you might as well go for it. I'd say finding the shortbed would be the hardest part of the deal if you have the skills to chop the frame.

[jzjames]

I just saw a magazine on the stands now on the how-to for shortening a frame for a shortbed. (With pictures - they were doing it on a Ch ##vy). I'll try to see if I can spot it again, but it wasnt Classic or Custom Classic Trucks I dont think....

[gmcjimmy88]

I just seen a show where they did that also. Dont remember the name but it was most likely Trucks, but I am not sure. If I see it again I will post it up.

[customcrewcab]

just backhalf it and tubb it.

[gmcjimmy88]

Dont quote me on this but I was thinking they had taken some material out of the bedsides from in front and behind the wheels. Basically made up the difference from both ends. I still cannot think of where I seen it.

[theskytoucher]

GMC you got that somewhere off this site i dotn know exactly where it is but it says that the total difference is 20in, 16 inches from the front of the wheel well 4 from behind the wheel well!!!!

[gmcjimmy88]

O.K. that could be true that I got it from this site. I know I seen it on T.V. somewhere as well. I want to say it was Stacey David on trucks that did it on a 69ish chevy.

[customcrewcab]

it was that show on the powerblock. i think trucks and they shorten a 64 or 65 chevy

[customcrewcab]

you could aways do this

http://www.fordification.com/galleries/ ... 0106&pos=4

[FORDification]

Here's a graphic I whipped up a while back, when comparing the bed sizes:

[gmcjimmy88]

it was that show on the powerblock. i think trucks and they shorten a 64 or 65 chevy

Yes that sounds right. I actually miss him on trucks not fond of the new guys.

[AlleyCat]

Although it's a big job shortening a frame is pretty straight forward. First off you will need the wheel base demension for a short bed truck.Next you will need a hard, level work surface.With the bed off you will need to remove the exhaust,driveshaft, and brake line to the rear wheels.Disconnect the parking brake cable and pull the wiring back under the cab.Scrape and wire brush the crud off of the frame from the back of the cab to the spring hangers.

Next, look at the top of the frame rails just behind the cab and you will notice the frame curves up then levels out.At this point you would need to make a reference mark on both rails.The marks must be exactly opposite each other.I spend some time doing this part as it is critical to make the frame square.Next measure from the reference point rearwards and make another reference point.Do this on both rails.Now measure from the forward mark on one rail to the rear mark on the opposite rail then measure the other 2 marks.The measurements should be the same if not go back thru the marking to find the problem.You should record all demensions as you will need them later.

Now measure from the front marks 3 inches to the rear.Make a mark at this point on both rails.These will be your first cuts.Before you cut though measure back from your cut marks the length you want to remove from the frame.According to Keith's graphic you would need to remove 17 inches of frame rail.

There are a couple different types of cuts you can use here.The first is a straight vertical cut.The second is an angled or "Z" cut.The "Z" makes a somewhat stonger joint by spreading the load over a greater area.The big disadvantage here is the "Z" requires additional space.It is also a lot harder to get the frame square again.

Whichever you choose mark both rails where they need to be cut then put jack stands under the rails near the rear of the cab.I like to use wooden wedges to put a load on the stands without raising the truck.Next secure the rear of the frame so it can't fall.Now make your cuts.A plasma cutter is the best tool for this job if you have one if not a cutting torch works just fine.

After you have made your cuts clean the sections up with a grinder.Now it's time to push the rear section forward and get everything realigned. I like to clamp a couple 1 foot long sections of 2 or 3 inch angle iron to the lower side of the rails at the cut.This makes it easier to get things aligned.

Remember the reference marks you made? Here's where they get used. Measure from the front to rear on both rails then opposite corners.Once you have it square then use a straight edge or construction level on top of the rails to make sure they are straight.Now clamp the loose ends of the angle iron and recheck your measurements.If all is okay you are ready to weld.

I make a short tac weld on both sides then make one last measurement check.I then weld the flanges first then the sides.After the rails are welded I recommend installing a reinforcement plate inside both rails.It should over lap the weld joint by 4 to 6 inches on both sides.Make sure the reinforcement plate does not extend on to the radius for the frame flange.

One final note here: If you are not 100% confident in your welding skills please get someone to help. If done correctly frame modifications will be as safe and strong as the original truck.If done incorrectly they can become an accident waiting to happen.Hope this helps.