Are all Longhorn frames the same?

[rs74]

I have started to look for a nice clean C30 to buy. I have come across a couple C20 Longhorns. I thought I had read that they had the same frame but wasn't sure if there was any variance in that. Are the C20 frames the same height and thickness of the C30? Does it matter is they are Custom Camper trucks or does the Longhorn make them a Custom Camper. Just wondering if I need to be taking the C20 LH into consideration along with the other C30 variations.

[71blksuper4x4]

Any 133” wb frames should be the same thickness but the c30 cab & chassis is the biggest (tallest/thickest) of all of the light duty frames.

[special-K]

The C/20 Longhorn is built off the C/30 frame. The only 133" WB frame is the C/30 frame

[rs74]

Originally Posted by 71blksuper4x4

Any 133” wb frames should be the same thickness but the c30 cab & chassis is the biggest (tallest/thickest) of all of the light duty frames.

Originally Posted by special-K

The C/20 Longhorn is built off the C/30 frame. The only 133" WB frame is the C/30 frame

Thanks. That answers my question then. I'll start looking at those as well.

[71blksuper4x4]

Originally Posted by rs74

Thanks. That answers my question then. I'll start looking at those as well.

Just so it's clear, the 133" frames should be the same and can fit a longhorn bed on them. The 157" c30 cab n chassis frames are stouter, but wouldn't be ideal for a longhorn frame. The rails are different on them.

[rs74]

Originally Posted by 71blksuper4x4

Just so it's clear, the 133" frames should be the same and can fit a longhorn bed on them. The 157" c30 cab n chassis frames are stouter, but wouldn't be ideal for a longhorn frame. The rails are different on them.

Understood. I am just trying to find a nice clean C30 for a project I am wanting to do. I am looking at all variants of the C30 and now C20 Longhorns. Thanks for the information.

[rs74]

I seem to recall someone posting the frame heights, thickness specs on the frames between C&C, and 133"wb. I am thinking may it was all frames from 1/2 ton all the way through one tons. Not sure what thread I saw that on though. Anyone have those specs?

[Killer Bee]

seems I recall reading the only difference between C30 and C20 longhorns was the HO72 rear axle and wider brakes vs HO52 axle, possibly thicker rear spring packs and bigger tires..

don't quote me but I believe the other options may include auxiliary springs, bigger tires, battery, alternator, etc. but still same frame..

since build sheets may be slim findings to compare C20/C30 longhorns vs cab n chassis trucks, perhaps comparing GVWR placards would be more readily available..

I can check the red 71 C20 longhorn tomorrow but have to wait until july to check the ochre 71 C20 longhorn, it's 1800 miles away..

third way might be to see if the frame part numbers are listed in the parts books.. I have a couple of books I can check if I can remember..

probably a hundred threads in here with the info you need, only trouble is finding them

good luck!

[special-K]

The 133" frames will be the same thickness whether cab & chassis or pickup

[Getter-Done]

Here is a link or 2 about frames not sure if all pertains directly.
But One search leads to another.

Link: http://67-72chevytrucks.com/vboard/s...d.php?t=180770

Link: https://67-72chevytrucks.com/vboard/...ht=frame+specs

[Dieselwrencher]

I just PM'd you. I know where a really, really nice 69 Longhorn project is. It needs a good home.

[Dieselwrencher]

Originally Posted by 71blksuper4x4

Any 133” wb frames should be the same thickness but the c30 cab & chassis is the biggest (tallest/thickest) of all of the light duty frames.

Originally Posted by 71blksuper4x4

Just so it's clear, the 133" frames should be the same and can fit a longhorn bed on them. The 157" c30 cab n chassis frames are stouter, but wouldn't be ideal for a longhorn frame. The rails are different on them.

This is true. I think where the confusion was is you said that the C30 cab and chassis is the biggest. This is only true if you have a wheel base of over 133". They made a lot of cab and chassis 133" trucks. I'm almost certain my 69 Milk truck is a 133" Longhorn frame and it even has 1.5 ton suspension. Even in 67 the cab and chassis was offered in a 133" WB, They just didn't offer the Longhorn in 67.

Like you said, you definitely can spot a 157" frame from the 133". The rear rails have an entire different shape so they could affix different beds/utilitarian structures on there.

[72MARIO]

The 1967 1968 frames have different leaf spring hangers I would.look at 1969 up because the replacement springs and shackles are more available.

[rs74]

What is the dimension difference between the Longhorn and C&C frames? Are they any taller and what are the difference in frame thickness?

[71blksuper4x4]

From an earlier Post from SSTIM

C20 Frames = 127" wheelbase
6.11" height
2.46" flange width
0.194" thick
3.71 section modulus

C20/30 (Longhorns) Frames= 133" wheelbase
7.20" height
2.77" flange width
0.194" thick
5.05 section modulus

C30 (cab & chassis) Frames= 157' wheelbase
8.18" height
2.97" flange width
0.224" thick
7.29 section modulus

Here is a pic of my 157" C&C frame

[rs74]

Originally Posted by 71blksuper4x4

From an earlier Post from SSTIM

C20 Frames = 127" wheelbase
6.11" height
2.46" flange width
0.194" thick
3.71 section modulus

C20/30 (Longhorns) Frames= 133" wheelbase
7.20" height
2.77" flange width
0.194" thick
5.05 section modulus

C30 (cab & chassis) Frames= 157' wheelbase
8.18" height
2.97" flange width
0.224" thick
7.29 section modulus

Here is a pic of my 157" C&C frame

This is exactly what I was looking for. I had come across this before just wasn't sure where. Thanks. A big reason I ask is that I wonder if doing a diesel swap if the frame without bracing would handle the torque. If I find and build one of these that is somewhat the direction I am think of going. I know some have built them without bracing while others have. I know there are brace kits and cross members for the cummins if wanted. Don't see much on Duramax swapping these though. Would rather keep the factory frame if possible.

[Dieselwrencher]

A friend of mine has probably 2 of the baddest Dmax swapped 67-72s on the planet. One is a 72 burb and has had a 950hp compound turbo duramax for a while. It has no frame mods. He has power tour'd it several times. He tows his race truck to events and still races the burb too. Back when he first built it, it had a MII type front suspension. He swapped back to a C10 front suspension. It has tubular trailing arms and the thing is an absolute rocket. Being around this thing made me a believer these frames will handle it. His is time tested as well.

http://www.67-72chevytrucks.com/vboa...d.php?t=472138

[rs74]

Originally Posted by Dieselwrencher

A friend of mine has probably 2 of the baddest Dmax swapped 67-72s on the planet. One is a 72 burb and has had a 950hp compound turbo duramax for a while. It has no frame mods. He has power tour'd it several times. He tows his race truck to events and still races the burb too. Back when he first built it, it had a MII type front suspension. He swapped back to a C10 front suspension. It has tubular trailing arms and the thing is an absolute rocket. Being around this thing made me a believer these frames will handle it. His is time tested as well.

http://www.67-72chevytrucks.com/vboa...d.php?t=472138

Too bad the Dmax didn't fit under the high hump. There is very little info out there on what it takes to fit that drivetrain in one of these trucks. Cool build though.

[Dieselwrencher]

Originally Posted by rs74

Too bad the Dmax didn't fit under the high hump. There is very little info out there on what it takes to fit that drivetrain in one of these trucks. Cool build though.

You could use a 4L85e. I know he has put one of them in a 68 burb with a low floor no high hump.