This is a '73 F-100 long bed with modified 302 and C4. There is a crossover on the frame (much like the tranny mount crossover but smaller) that sits at the rear ends of the radius arms. In fact, it appears that the same rivets that hold the rear mounts for the radius arms also hold on this crossover. It crosses over just a few inches behind the front of the bellhousing.

It is very difficult to R and R the tranny with this crossover in place. It's a tough struggle to force the bellhousing up and over this crossover (in fact, when I first installed the C4, I had to wack away at the tunnel in the floor to get it in. It also plays hell with my headers, which lean hard on it on the passengers side.

My idea is to cut and weld the part that crosses over to drop it a few inches. I assume this crossover is there to limit any distortion caused by pressure from the radius arms. So I am, of course, concerned about any safety issues.

Also, it appears in the Haynes Ford Pickup manual that the crossover was held in either by rivets or bolts. So I'm assuming that I could cut the rivets and replace them with bolts.

Any opinions? Thanks

 

I personally wouldn't mess with the rivets. Yes that crossmember is there to strengthen the radius arms and keep from flexing the frame there. I wonder if you could cut it out and plate each end of the peice (or the ends left on the truck) so the ends lap onto the existing peice(s), drill 2 holes in each end and put some 1/2" grade 8 bolts and locking hardwear in there That way you can unbolt and remove the CM to drop your tranny, and bolt it back up when your done

 

it is a pita but it keeps the entire front of the frame from distorting. i would leave it. i can install a c-6 no problem and headers with it there.

 

my 79 f150 has it and my crossmember and radius arm brackets are held on with grade 8 bolts. so I just remove a couple bolts and that cross member is out of my way to R&R tranny.

 

Thanks guys! Frankin-Truck, I like your plate idea! I doubt this crossmember stops distortion as much as the front suspension crossmember does-it's so small in compairison. I think it just acts as support for the radius arms as we said. I think your plate idea with good welds might work. Classic79, I'm not really sure it's rivets. I'll look closer.

 

polkat did you install the headers on your truck, and know there for a f-100
and that some one did not use car headers! I bought a 73-79 that some one
had installed car headers and they had to notch that little crossmember for
the car headers to clear it! I have installed headers on lots of 73-79 f-100
small blocks and that crossmember with the right f-100 headers always worked
very good.

heres a look at the cross member that used to always be a problem with headers! This is a 65 tranny crossmember, maybe something could be done
with the other crossmember that would be similar.

https://www.ford-trucks.com/user_gal...=79912&width=2






p.s The small cross member that you are dealing with should just bolt in like
has already been said, I see no problem with you modifying it!

 

Pro-Street/StateTK,
Interesting idea. Between that and Franken-Truck's idea I think I know what I'm gonna do. One last thing I think I should ask; Can I assume that with the I-beams on jack stands, if I remove this little crossmember, things won't move around a bit making it hard to get the crossmember back in? When held static like this, is there any pressure on the crossmember coming from the raduis arms or anywhere else that will make alignment slip a bit? Thanks!