I am new to this site, I have a 2001 ford ranger regular cab 4x4 flareside. The back half of the frame is rusted, so I am trying to see what frames I can use to replace the back half?

 

Welcome to the forum

Rangers from 1993 to 2011 had the same frames, they were made in 2 parts, front and back, the front had a few versions, 2wd, 4wd, regular or extended cab
But extended cabs and regular cabs the rear frame was the same, they both use the same 6ft bed, and 2wd or 4wd didn't matter

There were Long Bed Rangers, all were regular cab, they did have a different rear frame, axle was 6" farther back, you could change yours to a Long bed, but would need a new 7ft bed and longer driveshaft

Best years would be 1998-2003 with no rust, of course, spare tire mount was the same in those years and they had the EVAP mounting

 

So for a example a 2003 2wd extended cabs short bed will work on mine, what about the wheelbase, don't that matter?

 

Yes, it would work fine

For regular cab and extended cab the Front frame was longer for extended cab version, rear frame was the same for both
For 4x4 the Front frame was "boxed", in 2WD just "C" type frame rails
Any differences were all in the Front frame, with the exception of "long bed" ranger

 

Thank you.

 

How much of the frame is rusted ?

There is the extreme rear section replacement kit or is that there used to be !

I was just looking for the Frame Extension Kit without any luck, but I did see a lot of frame replacement happening; the frame can separate behind the cab and if you do the replacement that way you will need a short-bed frame section from behind the cab back.
Also, IF you use the Rear Frame Replacement method, which is a good idea to me, make sure... not to use grade 8 bolts; they are too hard and can snap not just stretch like grade 5 bolts... the key is to get a little larger grade 5 bolt than OEM Hole Size, to replace the Rivets.
Just thinking out loud !

 

From the bumper on the driver side up to about 5 inches under the cab is weak.

 

I think that's to far forward to do a rear frame swap, the front/rear frame joint is at the spring hanger for the leaf springs.

 

+1 ^^^

Rear frame is "cab back"

Seen here off the truck: https://www.ranger-forums.com/attach...t-img_0717.jpg
You can see the 6 Bed Bolt clips, the 2 in the front show where the bed ends behind the cab

Seen here on the truck: https://www.ranger-forums.com/attach...t-img_0605.jpg

Any part under the cab is part of the front frame

 

Sounds to me like you will need a completely different frame.

Get under the truck, test the portion of the frame that is under the cab from the connecting point of both halves to to the end of the bad section.
See just how bad it is, then decide if the under cab part can be welded to.
if that portion can not be fixed, you, IMHO, are **** out of luck and start looking for a new frame or new truck.

If the frame is unrepairable you need to determine if the body is worth the task and it won't be a "Walk in the Park" by anyones expectations.
A body change will require a lot of mechanical ability, the wiring will take time to decipher and make it work once it is all plugged in again and time !

I am not trying to turn you off to the frame fix/replacement idea but if the frame is not fixable and the cab show signs of wear, rust, beyond fixing... it is time for another truck.

Good Luck on your deciphering the job but anything can be done if you want to do it !

 

Thank you everyone for your help. I should have a update by next weekend.