Builds 86 Xtra Cab Build (4Wheelunderground 3 link front, 4 link rear and 3.4 swap) (7 Viewers)

[aztoyman]

The other thing I need to modify or fab a replacement for is the cross member I had to cut out to make room for the rear link brackets.

I need to make sure I get my E-brake linkage in there somehow as well.

This is where it used to be.

 

[aztoyman]

Once these are addressed, I need to pull the engine and trans so I can weld the backside of the shock towers and steering box reinforcement, finish motor mounts. AND deal with the big F'n notch I cut in the frame rail.

The good thing about all that is it's just basically welding.

Oh, and find a place for a fuel tank.

That's the new plan.

 

[ntsqd]

Connecting those two brackets with some structure will add strength to the whole frame. I'll suggest that it not be a flat plate unless there really is no other option that doesn't compromise clearance. Even then I'd be hesitant. Try for a tubular or boxed structure if at all possible. The taller the better.

I would try to run the OEM trans mount as one option.
The other option is to use the plate that is bolted to the rear of the t/c and add a cross-ways round tube to it. Use FJ60 rubber leaf spring bushings (I got mine from Kurt) in the tube. A tab on each side and a long bolt complete the mount.
This is the SBC mount that I built using these, I sized the length of the tube to work with the stock mount part that bolts to the Chevy block:

For the trans mount I made a new mount using the FJ bushings that exactly replaced the stock GM trans mount. The best pic that I have of it isn't very good for showing it's details, but here it is:

 

[aztoyman]

@ntsqd, The TG skid plate mount does use OEM mounts at the T-case and why I'd like to "adapt" it to work rather than the one holding it in place right now. The link brackets are attached to the frame exactly where the mount used to go.

I was thinking of cutting the skid plate with mounts to fit between the link brackets and make it bolt on there. Essentially tying it all together across the span of the frame again.

As far as the horse collar cross member, I was either going to see if I could cut and fit it to be where it was originally. Which is right on top of the link brackets. Or fab something similar.

Would it hurt to move it in front of or behind the link brackets?

I don't need that muffler hanger on it but I will need to make something work for the E- brake cable mounts on the passenger side of that cross member. Because of that, I was thinking I could move the cross member slightly forward to keep that close to it's normal location.

 

[ntsqd]

If the TG skid-plate can be made to bolt frame rail to frame rail, and bolt to the link brackets while clearing the links for their full range of motion while also supporting a stock trans mount then that is what I would do. That way everything is tied together and supporting each other.

Tying the rear link brackets together the same way with something like the horseshoe or a similar fab'd cross-member looks like a really good idea to me. If it's simple enough to alter the horseshoe to fit I'd use it. Fore or aft of the link brackets will be good for the frame, but not for the brackets. I'd try to tie them all together if possible.

 

[aztoyman]

Looks like I'd need to move it at least slightly forward.

 

[aztoyman]

I can NOT attach the TG skid plate to the frame anymore. The link brackets are using the mounting holes instead. AND fully welded. I was thinking that attaching to the link brackets, tying them together might work. Essentially spanning the gap between the link brackets. Not a good idea?

 

[bkg]

I can NOT attach the TG skid plate to the frame anymore. The link brackets are using the mounting holes instead. AND fully welded. I was thinking that attaching to the link brackets, tying them together might work. Essentially spanning the gap between the link brackets. Not a good idea?

my tacoma has the TG mount w/ 4WU kit... but it wasn't an easy thing.

I really like this design. Maybe something to consider.

 

[aztoyman]

Thanks for the pics bkg. Kinda what I want to do. Sort of. I was thinking of cutting out the center of the plate and attaching as a bolt on between the link brackets. IDK, I'll figure something out.

I REALLY appreciate any and all input. Lot's of good ideas out there I'm sure. Plus, ntsqd has the engineering background to tell me if I'm messing up or not.

I just got home so I'm going to tackle the "horse collar" cross member first. At least that one is relatively straight forward.

 

[gnob]

you're on the right track dude.
engineers talking to hear themselves talk

 

[ntsqd]

I can NOT attach the TG skid plate to the frame anymore. The link brackets are using the mounting holes instead. AND fully welded. I was thinking that attaching to the link brackets, tying them together might work. Essentially spanning the gap between the link brackets. Not a good idea?

I hadn't really looked at just how structural the link brackets are until now. I would try to get the bolts that attach the part spanning the gap between the brackets to be in two planes that are more or less 90° to each other. The further apart that they can be the stronger the joint will be. There's always limits to what can be done or even should be done. Do you have a pic of what the front link brackets look like from the bottom? I did a qwik look and didn't see one previously posted.

As to the horse-collar I don't see a problem with it being a little further forward if that clears everything.

 

[aztoyman]

Here's a pic from 4WU instructions page. Almost exactly what I'm talking about. Here the TG plate is cut to use as a skid plate and they have the FROR crossmember holding the cases in.

Why cant I ATTACH the plate to the link brackets with bolts and keep it as a mount. Not just a skid plate?

Pic coming. I couldn't link it.

 

[bkg]

Thanks for the pics bkg. Kinda what I want to do. Sort of. I was thinking of cutting out the center of the plate and attaching as a bolt on between the link brackets. IDK, I'll figure something out.

I REALLY appreciate any and all input. Lot's of good ideas out there I'm sure. Plus, ntsqd has the engineering background to tell me if I'm messing up or not.

I just got home so I'm going to tackle the "horse collar" cross member first. At least that one is relatively straight forward.

this is the finished product... it's Generalee7's Tacoma build from PBB.

I really like the idea of tying the link brackets together.

 

[aztoyman]

Yeah, probably what Brian was talking about when he mentioned tying the link brackets together. But the pics I saw were the ones tying them together front to rear. Not across like this.

Again, THANKS for the pics and ideas.

 

[ntsqd]

I see no reason why the plate can't be used like how you want to. I'd encourage it. Build structure on the plate to bolt to the brackets.

 

[aztoyman]

No going back now. I think what I want to do is possible. I have a plan and made a little progress. I'll post more pics and details tomorrow.

 

[gnob]

been there.

 

[aztoyman]

Yikes! I've been down THAT road too. I don't remember how many times I tried before I figured it out.

Hey, I saw a steering box pic?? Which reminds me, I have to drill a different hydo assist port.

 

[gnob]

Yikes! I've been down THAT road too. I don't remember how many times I tried before I figured it out.

Hey, I saw a steering box pic?? Which reminds me, I have to drill a different hydo assist port.

my original post didn't do what i wanted. lol

dont let the balls out.

 

[aztoyman]

Here's a pic of the cut skid plate mounted to the T-cases. I made a cardboard pattern and cut out a piece of 1/4 plate to span that gap as a flange to weld to the link bracket.

There's JUST enough room to add a matching flange to the skid plate. I cut that out of 3/8 plate.

I clamped both flanges together and drilled them out for the original T case mounting bolts.

I put an adjustable jack stand under the skid plate to push up against the flex of the mounts. The weight of the plate was stretching the mounts down and I need to maintain my 4 degree engine/trans angle. I also made sure the output flange is centered in the frame and that the transmission is level side to side. No rotation. I spent more time than I expected trying to set this up.