Back to the dual case set up:
So, after I couldn't get the trans working, I went with the Inchworm adapter, like I said.
This adapter has some plusses and minuses. Its got the option to clock, which is good, but I didn't do that, but it also has mounting patterns for the 4.0 transmissions, which kinda sucks. They provide set screws and tell you to seal every non-used hole with silicone. This is okay, but not brilliant, IMO. I'd rather have an adapter with only one set of mount holes for the transmission.
After bolting everything together (pretty self explanatory so no pics of that) I got to building a new cross member.
Got a press brake, so that was put to use matching up the mounting locations.
Why two? The factory set up has the mount on the transmission for the 3.4 trucks, but the 22re trucks, the mount was on the tcase, as you can see.
A person in our local club simply used the front trans mount when he went duals, and after about 5 years of use, the crawl box case split apart on the trail.
While I don't have specific data, my hypothesis here is that the crawl box is designed to take load through the lower mount, but in the 3.4 trucks, its taking all of the torque where it mounts to the adapter. This, coupled with the added weight of the factory tcase and adapter behind it means breakage is likely when using factory mounting spots.
By doubling up, I also increase the resistance of the tranny side mounts, taking load from the engine mounts, which *should* be less likely to break this way.
Once I had the mount set up figured, I build a crossmember skid around it.
I was going to remake all of the crossmembers, but I was heading to Moab in a week, so I opted to get done quickly. I cut the front factory crossmember and notched it for the tubes. I then just plated up to the rear.
One thing I plan to change: I kept the factory weight that is bolted to the tcase for what I assume is vibration damping. I thought that was a good idea, but I don't think its doing much with the double mounts on the trans and tcase. So I plan to remove it, and flatten out the crossmember.
To keep it simple at first, I just lost my cup holder as is common.
However, after about 6 months of driving like that, I hated it. The shifter hit my leg and I wanted my cup holder back.
So, back to the drawing board.
As with my transmission above, I knew that I could retain my factory j-shift by using solid pivots, and keeping the linkage pivot between the shifter pivot and the handle. *If you put the shifter pivot between the handle and the linkage, you reverse the patterns* (Just in case anyone wants to do that, I do this in a later modification of the front case shifter)
I fabbed a plate which sits on 3/8" spacers and bolts to the transmission shifter as well as the front two mounts of the front tcase shifter. It has to be spaced up to clear everything. With longer bolts, the shifters can be torqued properly.
And how it works:
Made a cap piece to clear the shift nub. I'd like to get rid of this at somepoint. Still working on how to do that.
And finally, I tried to make the front shifter work (using a similar link), by coming up through the boot next to the trans shifter. It had to be up that far to clear the rear case shifter when the rear case is in low, and the front in high.
Got my cup holder back, but the hole in the rubber boot made for a noisier cabin, and I never liked how janky it looked. So a new fix was in order. But not right away.
So, after I couldn't get the trans working, I went with the Inchworm adapter, like I said.
This adapter has some plusses and minuses. Its got the option to clock, which is good, but I didn't do that, but it also has mounting patterns for the 4.0 transmissions, which kinda sucks. They provide set screws and tell you to seal every non-used hole with silicone. This is okay, but not brilliant, IMO. I'd rather have an adapter with only one set of mount holes for the transmission.
After bolting everything together (pretty self explanatory so no pics of that) I got to building a new cross member.
Got a press brake, so that was put to use matching up the mounting locations.
Why two? The factory set up has the mount on the transmission for the 3.4 trucks, but the 22re trucks, the mount was on the tcase, as you can see.
A person in our local club simply used the front trans mount when he went duals, and after about 5 years of use, the crawl box case split apart on the trail.
While I don't have specific data, my hypothesis here is that the crawl box is designed to take load through the lower mount, but in the 3.4 trucks, its taking all of the torque where it mounts to the adapter. This, coupled with the added weight of the factory tcase and adapter behind it means breakage is likely when using factory mounting spots.
By doubling up, I also increase the resistance of the tranny side mounts, taking load from the engine mounts, which *should* be less likely to break this way.
Once I had the mount set up figured, I build a crossmember skid around it.
I was going to remake all of the crossmembers, but I was heading to Moab in a week, so I opted to get done quickly. I cut the front factory crossmember and notched it for the tubes. I then just plated up to the rear.
One thing I plan to change: I kept the factory weight that is bolted to the tcase for what I assume is vibration damping. I thought that was a good idea, but I don't think its doing much with the double mounts on the trans and tcase. So I plan to remove it, and flatten out the crossmember.
To keep it simple at first, I just lost my cup holder as is common.
However, after about 6 months of driving like that, I hated it. The shifter hit my leg and I wanted my cup holder back.
So, back to the drawing board.
As with my transmission above, I knew that I could retain my factory j-shift by using solid pivots, and keeping the linkage pivot between the shifter pivot and the handle. *If you put the shifter pivot between the handle and the linkage, you reverse the patterns* (Just in case anyone wants to do that, I do this in a later modification of the front case shifter)
I fabbed a plate which sits on 3/8" spacers and bolts to the transmission shifter as well as the front two mounts of the front tcase shifter. It has to be spaced up to clear everything. With longer bolts, the shifters can be torqued properly.
And how it works:
Made a cap piece to clear the shift nub. I'd like to get rid of this at somepoint. Still working on how to do that.
And finally, I tried to make the front shifter work (using a similar link), by coming up through the boot next to the trans shifter. It had to be up that far to clear the rear case shifter when the rear case is in low, and the front in high.
Got my cup holder back, but the hole in the rubber boot made for a noisier cabin, and I never liked how janky it looked. So a new fix was in order. But not right away.
