Forest Truck 1 – Disassembly // How to Build a Cab Lifting Jig

Cramming this much work into a reasonably palatable video required some chopping but I think 10 minutes is about the right length. The video is far from exhaustive but in my opinion this isn’t the interesting part. Fixing, restoring, improving, and modifying the bits of truck as it goes back together is what keeps me in it and I’m really excited to get to that.

One part of this video that might beget more information are the 2×4 contraptions I built for the cab and bed removal. This process will be largely identical for most any pickup truck and I specifically wanted to elucidate on the lifting jig for anyone disassembling a truck with a similar set of tools, i.e. an engine hoist.

Cab Lifting Jig

Pickup cabs are pretty light once they’re all stripped out but unless you call over a bunch of friends you’ll still need a way to lift it up off the frame. An engine hoist is more than strong enough and has enough travel but they can’t reach over the top of the cab. The solution is to build a jig to support the upper door jambs and lift from inside the cab.

I started by building the pieces to tie into the door jamb. If your jambs are relatively flat (more likely if you have a truck from the ’60s or earlier) you may just be able to trim lumber to land nicely upon that. If you have a late model truck the sheet metal might be a bit more complicated. My design for the lifting jig was simple but strong. It keeps most of the weight of the cab off of the hardware and in compression joints between lumber. The tall section of the 2×6 cross pieces is almost excessively strong. One thing to consider during the whole process is how nose heavy cabs are: much more structure in the firewall than the back wall of the cab. I didn’t support the cab quite as far forward as I would have liked to. You can also consider throwing some ballast towards the back of the cab to help keep it balanced.

I used some chunks of 2×4 and metal braces for the parts that contact the jambs. A little bit of table saw work helped to clear the pinch seam and the radius of brace. Then I clamped it into position.

Then I found the angle of my V support and made a little drawing for the stanchions. A square aided the transcription and use your choice of saw to cut it out of a 2×6.

I left about 6″ below the bottom of the V because I’ll be using 2x6s as the cross pieces.

I clamped the stanchions into place and screwed then into the Vs. Later I added a few screws down from above just for good measure. The separation between the stanchions is dictated by the width of your cross supports, width of the engine hoist boom, and any extra space you want in there.

I used a bit of clever clamping to make a shelf for the crossbar on one side so I could slide it in from the other side and get it clamped into position. Remember that the whole assembly has to be held up to the truck.

After they were good and screwed in I found the center, drilled my holes for the bolt, and it was ready to get bolted up to the hoist.

The lifting went okay but as you can see in this picture I had too much weight forward. Cabs are very front heavy and next time I lift I’ll reposition the stanchions to move the center of gravity back a few inches.

Dollies

I didn’t take as many pictures of the dolly construction as maybe I should have. They’re straightforward construction and consist of a few core components: some kind of bottom frame to support the casters, vertical stanchions, then some method of affixing the component to the dolly. For the cab dolly I screwed down through the mounting holes into my vertical stanchions. For the bed dolly I was able to build the dimensions of the dolly so it dropped in nicely around some features on the underside of the bed and it couldn’t slide around.

A dolly in action.

A closeup of some of the construction bits. I had six dollies from a cheap creeper so I threw the extras in.

A few things to keep in mind while you work on these:

  • Your dollies have to be strong enough to support the weight of the component but also bear in mind if you want to be able to sit on it and with how many tools. I plan on sitting inside the cab while I do some sheet metal work.
  • Remember that pushing your stuff around the shop and maybe hitting something with the wheels could put a lot of side forces on your dolly. Add some diagonal supports and make sure the body component can’t slide right off.
  • One of the cheapest quick ways to find high capacity castors is buying furniture dollies. Go to a big box store and you’ll find a moving dolly is about $20 and rated to 1000 lbs. Go over to the castor section and see what 4 250lb castors cost.

If you’re very unfamiliar with woodworking this is a low risk and low investment project to dip your toes in. I used a a compound miter saw for most of my cuts but I have built similar 2×4 constructions with a miter box clamp and a hand saw. Even a cheap corded drill would be enough for driving the screws but I used a 12v Bosch drill and there are other 12v drills out there for you to consider.

Good luck and have fun in the shop!

You may also like...

Leave a Reply

Your email address will not be published. Required fields are marked *