Difference between 4x4 and 2wd frames-Look here

[1969k10stepside]

I see this asked alot,I have pics comparing the two frames and Im gonna share them for people to see the difference.
First pic is a lwb 2wd frame on my old 71 c/10.Second and third are of my 69 4x4 frame two years ago when I got it.I am gonna add pics of my swb 4x4 frame shortly also for better pics

[1969k10stepside]

The 2wd has a noticeable difference in the back of the frame for the coils as to the straight 4x4 frame for the 52"(56" for 67-68) leaf springs.

[Terraizer]

What about the differences up front? My 1971 C-20 has leafs just like the 4x4 you show not the coils. I know up front the front cross member will be different but what about the frame rails themselves inf ront of the cab?

[1969k10stepside]

I am not sure on the front.I know the 4x4s have the brackets for the bushings and shackels for the front springs,and under the rad. mounts there is a riveted bracket for the front spring hanger.I dont know how you can convert it for that

[GMCMAX]

Front's not hard to convert on a c10 if you get all the brackets, just drill for the extra holes and bolt on with proper size grade 8's. Ya do have to flatten or cut out the dimpled out places where the e brake cable and holder goes.

[HarleyHogRider]

I so want to thank you for this post on the difference in frames. I have spent hours and hours trying to convince Classic Performance Products (C-Notch Kits 6372CNK-HD) and McGaughy's (C-Section Kits 63167) both of which I ordered through Summit that their claims that these fit every Chevy and GMC truck from 67-72 was false advertisement and that they only fit Coil Spring Truck frames not Leaf Spring Frames. They do not fit GMC frames with leaf springs. I finally wound up fabricating my own C-Notch's for my 70 GMC 3/4 ton C-2500 frame. So frustrating ordering stuff they claim will fit and it doesn't. I finally discovered the same difference you did in your post. VERY, VERY Valuable information to put out there. I converted my 3/4 ton C-2500 GMC to a Chevy C-10 suspension in the front and rear to get the fancier wheels in a 5 lug and not an 8 lug. (1000 HP, 540 CI, Vortech V7, Abruzzi TH 400, Strange Engineering Ford 9 inch, converted to Coil Overs)

[palallin]

Is this 2wd vs 4wd or coil vs leaf?

[special-K]

More like coil 2wd vs 4wd. The 2wd leaf spring frames don't bubble out like the coil spring ones do, but they have a taper behind the axle that 4wd frames don't. We need a picture of a leaf spring 2wd to complete this thread.

I know in the front hump in the frame, over the front wheels, the 4wd frame rises about 1" more. But this makes no difference when doing a 2wd to 4wd conversion.

All other dimensions are the same, so all the 4wd components fully swap to a 2wd frame.

Suburban frames only differ from LWB pickups in some body mounting brackets. I wish I had gotten copies. But when a friend wanted to put a 4wd chassis under a Panel truck he came up with diagrams with all the specs for these GM light trucks and these are things we found out. It was years ago and I never checked on actual vehicles, but these were GM drawings. He ended up donating a 4wd Suburban to complete the project

[HarleyHogRider]

Originally Posted by palallin

Is this 2wd vs 4wd or coil vs leaf?

Is this 2wd vs 4wd or coil vs leaf?
_________________
'69 Longstep K-10: 327/SM465/T-221/Closed Knuckle Dana44/12-bolt.

Not sure if your post is a question because of my post. But this thread started out as Re: Difference between 4x4 and 2wd frames-Look here

Mine is a 2wd frame and I was attempting to show the difference between two different kinds of 2wd frames. That is, the difference between leaf and coil 2wd frames which are also different than 4wd frames.

[chewychevy67]

This is my 67 swb 2wd leaf spring frame.

[Bob B.]

My '67 GMC C-2500 frame is similar but longer than chewychevy67's. special-K is right, the 4X2 leaf spring frames are contoured towards the rear, not straight like the 4X4's

[57taskforce]

It’s Also probably worth noting that the 2wd frames have ebrake cables and holes right where the rear front spring spring hanger goes. The holes have to be filled with plate and then the correct holes drilled for the hanger when converting a 2wd to 4x4.