How to replace frame crossmember?

[budman k20]

Hi,

I purchase a 73 front cross member for the sway bar mounts from a board member to put on my 72 K20 ... now I want to install it! What does everyone do? Bolt it in ...or does it need to be riveted? Seems like bolts would work loose over time, but riveting seems like a lot of work! Anyone done this before and if so how did you do it?

[69 longhorn]

The sway bar brackets were originally riveted to the frame horns, but you can bolt them on. I use grade 8 bolts, with pinch lock nuts(they dont work loose). On the lower arms, the "C" brackets that hold the bushings for the sway bar, were bolted from the factory. crazyAL

[budman k20]

Hi Al,

Your suggestion sounds correct for a 2 wheel drive but I have a 72 K20 and I am using a 4x4 cross member from a 73 K20 that has the brackets as part of the crossmember so I have to replace the entire front cross member. That is why I questioned using bolts.

[69 longhorn]

Originally Posted by budman k20

Hi Al,

Your suggestion sounds correct for a 2 wheel drive but I have a 72 K20 and I am using a 4x4 cross member from a 73 K20 that has the brackets as part of the crossmember so I have to replace the entire front cross member. That is why I questioned using bolts.

Oops, I missed the K part! crazyAL

[LockDoc]

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I have done three complete crossmember transplants, used grade 8 bolts with no problems. Mine have been 2wd but it shouldn't make any difference....

LockDoc

[JimKshortstep4x4]

The 73 crossmember is not a bolt in replacement, so you will need to modify the way it is mounted. If you look at it you will notice that it mounts at a different angle from the 72 K-10.

Jim

[chas350]

Originally Posted by JimKshortstep4x4

The 73 crossmember is not a bolt in replacement, so you will need to modify the way it is mounted. If you look at it you will notice that it mounts at a different angle from the 72 K-10.

Jim

^^^x2

[budman k20]

I did a quick look at my current cross member and it looked like I would have to drill an extra hole one each side to mount the 73. If I remember correctly the 72 has only 4 rivets. The 73 has 6 so I was thinking that I was going to use the existing four holes in the frame and drill two new ones in the bottom of the frame rails. From your comments it sounds like that will not work? Do you have any suggestions as to the best way (which holes to use) to mount the 73 cross member? I can't think of anything that be in the way if the 73 cross member is at a different angle? This may not be as big of a problem on a 4x4 as there is a lot of room because the engine is set back so far. Sounds like some people have had good luck with grade 8 bolts instead of rivets.

[wildwilly4x4]

I put an '86 crossmember in my '72. It came out of a 1 ton, so I dunno if that mattes, but it didnt want to line op with any of the holes in my frame. I just buzzed it in with a wire welder.

[OrrieG]

I have used grade 8 hardware for anything bolted to my frame included the motor mounts, spring perches, tranfercase crossmember, etc. I drove it offroad and around town for 12 years averaging 6K miles per year with no problems. If you are really worried about it use self locking nut and double nut it for extra safety.

[cliffy]

I am putting an 80 into a 60, drilling new holes and using grade 8 and lock nuts.