DIY4X crossmember fitment
 

Alright, here's my dilemma. I'm in the parts gathering phase of converting my 1970 C30 to a K. I have a 1988 V30 donor truck that I'm going to use the axles, trans and transfer case out of. Anyway my question is about the DIY4X first gen cross member.. its height in particular.

My x member 'C' pieces are too tall to fit inside the frame 'C'. Not much, but enough to matter. maybe .125". Has anyone encountered this issue? I put a caliper on Kerts 'C' part and came up with 5.25" tall. Can I persuade one of you gents with a k10/20 frame to measure inside the channel at the x member area? I assume (famous last words) that the frame would have the same height dimensions from the cab forward regardless of 10/20/30 series.

Now this issue may be because I have a 1ton frame?? but I find it odd that my frame would be SHORTER than a 1/2 or 3/4 ton. I called DIY4X this morning but Kert was out with the flu. Any help would be appreciated.

Thanks,

Re: DIY4X crossmember fitment
 

Are you talking about the motor cross member or the trans/transfer case cross member?

Re: DIY4X crossmember fitment
 

Engine cross member. Should have been more specific.

Re: DIY4X crossmember fitment
 

I have a 72 K10 in the shop. I'll go measure it.

Re: DIY4X crossmember fitment
 

On the front side of the cross member this is what I got. Drivers side is right at 5 in. Passenger side is at 5 1/8. My cross member is at the v-8 location so the measurements were taken between the v8 location and the 6 cylinder location.

Re: DIY4X crossmember fitment
 

I think the C30 frame height from top to bottom may be greater than the 20. Ignore this, just re-read what you posted. Based on JC's measurements your x member is too tall for his frame also?

Re: DIY4X crossmember fitment
 

This is true **from the bell housing area rearward**

Jfc just confirmed my suspicion, it looks like all 1/2, 3/4, and 1ton frames are going to be the same from the firewall/bell housing area forward. Its beginning to look like Kert sent me a faulty piece that was fabbed too tall.
I have read nothing but rave reviews about this product, and ultimately decided to go with it over the ORD equivalent. I will contact Kert and work on a resolution.

BTW thanks JFC for your help!

Re: DIY4X crossmember fitment
 

No problem, anything to help. What is the height of the cross member you have?

Re: DIY4X crossmember fitment
 

Correct. My DIY4x piece is measuring 5.21"-5.25" tall. So basically its roughly 1/8" to 1/4" to tall. I believe I read elsewhere on this site that someone got the same part and it was way too short, and had to use shims to make it fit snug.

Re: DIY4X crossmember fitment
 

Just something to try if you haven't already is bolt together leave loose install then tighten. If that's a possibility my factory cross member was plenty tight and that's how I got it to work.

Re: DIY4X crossmember fitment
 

give kirt a call at diy4x

he is super cool to deal with and will help you out .

i have lots of his stuff .

Re: DIY4X crossmember fitment
 

That is impossible with the issue I have. the cross member is designed differently than stock and will not even begin to fit in the frame.

Re: DIY4X crossmember fitment
 

Bummer. Are you going to start a build thread when you tear into the conversion. Looks like a sweet truck if that's the one in your avatar. Look forward to seeing more.

Re: DIY4X crossmember fitment
 

A visual. The inner 'C' part is 1/4" too tall to fit inside my frame 'C'

Attachment 1748106

Re: DIY4X crossmember fitment
 

K makes sense now after seeing it put together.

Re: DIY4X crossmember fitment
 

Yep. I will start a build thread here once I really dig in. I pulled the engine Saturday and its ready for the 2wd junk to be ripped out. It is the truck in my Avatar, I will upload some better pictures soon. BTW Blue Bullet I'm watching your build closely as it is similar to what I have in mind for my build.

Re: DIY4X crossmember fitment
 

Cool sounds like you have the same donor as mine also. Don't hesitate to ask questions if there is something I should be pointing or explaining what I didn't.

Re: DIY4X crossmember fitment
 

Blue, while we are on the subject, I have a question! Did your 4x4 cross member line up with any 2wd motor mount holes in your frame? Or did you have to drill new? In my case, the aftermarket x member doesn't appear to line up with any existing holes..

Re: DIY4X crossmember fitment
 

I welded everything shut. Then put drivetrain in and cab on. I could see roughly were the front hole was so I started close to that then dialed it in from there. The first test run I had original shifter but V30 linkage. I didn't like that position because I wanted to use the original pipe to radiator and 4x4 shroud. That's when it dawned on me about the linkage. Once I got it positioned according to original high hump hole and original shifter with linkage that's where I was happy with location. I think I could still go big block and have good clearance. If you need some measurements let me know.

Re: DIY4X crossmember fitment
 

Answered already but I did the 4wd swap thing to an 89 crew cab. I had access to a junkyard with 1/2, 3/4, and 1 ton 4wd trucks. The engine crossmember is the same
Between them. Maybe by 1/4”....

Re: DIY4X crossmember fitment
 

I just spoke with Kert @ DIY4X and let him know my issue. He measured some of his in stock parts and he says they are correct. The height is supposed to be just shy of 5.25".. :confused:

Re: DIY4X crossmember fitment
 

What are you going to do?

Re: DIY4X crossmember fitment
 

I think what is throwing things off is the thickness of the frame rails themselves. A c30 frame had thicker material for rails than a 1/2 or 3/4 ton. I might be just enough to cause issues. Trevor

Re: DIY4X crossmember fitment
 

Hmmm.. That's a good point. I will pull a thickness measurement on my frame rail ASAP. The only thing that has me confused is JFCs measurements on this K10 frame (which is what the cross member is designed for and advertised to fit). His measurements are the same as mine on the C30.

Re: DIY4X crossmember fitment
 

I will also measure my 157" Cab and Chassis C30 frame rails. That way we have a definite answer. I think we need to measure all the same way, in between the frame rails. Just so we are all the same. Trevor