Which is correct 1985 k5 blazer transmission crossmember

[Lorenblazerk5]

Hi, trying to determine best practices for the mounting the transmission x member. I have two photos. One showing direct attachment to frame. The other showing spacer directly to frame. What is the proper way to mount?
1985 Chevy k5 Blazer 4" lift currently using spacer (which is causing a crack in frame)
Thanks!

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[bucket]

The spacers aren't supposed to go between the frame and crossmember, but people often put them there.

 

[nvrenuf]

Spacer between can lead to cracking or a bending in that area if the crossmember ever hits anything.

Also, lowering the crossmember will make the front driveshaft operating angle worse.

 

[WRW86]

Spacer between can lead to cracking or a bending in that area if the crossmember ever hits anything.

Also, lowering the crossmember will make the front driveshaft operating angle worse.

I think some guys put the spacer between the support and the frame to help compensate for the rear lift blocks but didn't consider what it did for the front driveshaft.

I think mine came from the factory with the spacers above the frame but gm illustrations seem to show the spacers below the support as per the first photo. I don't think it matters what side the spacer is on, as long as it isn't between the support and the frame?

 

[Lorenblazerk5]

Thank you for the comments. Here is the results from the way its currently mounted. Any comments on how to repair this frame crack?

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[bucket]

Thank you for the comments. Here is the results from the way its currently mounted. Any comments on how to repair this frame crack?

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I'd knock it back to flush, then weld it top and bottom. Then grind the welds smooth. Then cut a plate to fit on top of the lower frame flange, and pre-drill the crossmember holes in it. Then you can bolt it into the frame and weld the plate in. Then of course, put the crossmember back in.

 

[Lorenblazerk5]

Would you drill a relief hole at end of crack then weld up? thx

 

[Jawzjeep]

6 inch lift on my 91 sub and the crossmember stayed in stock location with spacers above the frame

 

[bucket]

Would you drill a relief hole at end of crack then weld up? thx

You can. It certainly won't hurt. When properly welded, it ain't gonna matter though, imho.

 

[ali_c20]

You can. It certainly won't hurt. When properly welded, it ain't gonna matter though, imho

I learned from an experienced welder that you should drill the end of the crack. Releases the stress and the welds go through. Also grinding a groove along crack to get penetration through the whole material helps.

 

[bucket]

I learned from an experienced welder that you should drill the end of the crack. Releases the stress and the welds go through. Also grinding a groove along crack to get penetration through the whole material helps.

Right, but with good penetration, that area where the hole was drilled is just going to be molten anyway.

What I always do is vee out the crack and then go a little past where the crack ends, then burn it in good.