The Stovebolt Site Forums The Shop Area Paint and Body Shop Shimming Cab ?

This is my first post ever on any social platform, please chime in if I am off the rails.
I purchased a 1950 3104 5 window in 2001 and proceeded with a frame up restoration. Then decided to go in business for myself 2003 so I put everything on hold. Now that I have retired in 2023 it's time to finish what was started some 20 years ago.
For some reason the cab is a heavy 5/8" to 3/4" low on the passenger side. All parts on the frame and suspension have ben replace with new. The cab has a new floor board and is level and square. It measures from the rear window frame to the floorboard within a 1/16" on both sides. (that was Luck). All new cab mounts shimmed to factory specs. Seems I may have a little OCD when it come to my truck.
My question is how much can the cab be shimmed to overcome the leveling issue before any problems with the front fenders and hood?

Thanks, Red

Welcome to Stovebolt, Red.

Is that 5/8 to 3/4" low as measured from the frame or from the ground? That will make a difference. The Factory Assembly Manual Section 1, Sheet 3.12 specifies 7/4" between cab floor and frame at the rear cab shackles. It should be the same on each side. the FAM also specifies 1.83" +.03"/-.00" frame to bottom of floor at the front mounts on Section 1 Sheet 3.09. Also should be the same side to side.
With that much difference, it sounds like your issue may be with the suspension.

You should head over to the Welcome Centre and introduce yourself and your truck. Tell us a little about yourself and your truck, such as how you acquired it, and post some photos as well (We love photos of old trucks )

I will check the cab height from the frame, and head to the welcome center. It may take me a minute to figure out how to post photos.

Thanks, Red

Yeah welcome here. Sounds like your an old hand at this now. The only thing off the rails it sounds is that cab.

The 5/8 to 3/4 low on the passenger side measurement was from the ground. The cab mount clearances are as follows. RR-1.82, LR-1.87, RF-1.94, LF-1.92. all measured with an inside mic. The only thing left to change on the frame are the front springs. I did not change them when I rebuilt the frame was because I could not find any that were broken. Is it possible that they may be weak enough to cause the cab to be low on the passenger side?

Red

Yes springs can definitely cause that. Especially if the previous owner was a BIG guy. I new a kid who owned a Model A that listed badly to the passenger side. It turns out he had bought it from a guy known as Tiny and had turned the transverse springs around to correct the serious list to the drivers side. 😁

Great I will have them changed shortly and see if it helps. Next question is what about building things to hold the doors, fenders and a rotisseries for the cab and this old back. I noticed under the Flickr above there was a dandy.

Thanks Red

If you're referring to my Flickr photos, I built that rotisserie for my cab. It worked out well, and the brackets that I fabbed for the doors went to another stovebolter for his use. It was very helpful in restoring my cab.

I have some sketches for the brackets if you would like them. They bolt to the hinge and striker locations. The other parts were engine stands that I picked up for $50 each. That plus some square tubing finished off the materials.

Yes I would love to have a copy of the door brackets, The stands i can get from harbor freight.

Thanks Red

Kevin, I’m sure allot of other ‘bolters would benefit from that drawing. Please post!

Phil. Good suggestion. Posted a full rotisserie build thread HERE.

Thanks Kevin, great job. Maybe in the future I can convert it into a “Tech Tip”!

Hey Red, did you ever sort this out? I fitted my cab to the frame this past weekend and got similar results to you. Didn’t break out the mic, but got just under 2” in front and rear between the frame and bottom of floor.

Problem solved, replaced the 2 front leaf springs and now the cab is level side side and Happy. I do have anther question. I do believe the clearance for the rear cab mounts are 7/4" or 1.75".
My FAM shows per section 1 sheet 3.12 that the clearance to be .76 +.06. that's an 1" +- difference from the front mount. Do you think it's a typo in the FAM and they forgot the inch?

Red

Glad you got it sorted out with the replacement springs.

I saw that difference in the fam, but haven't gotten to that point on my truck yet. I "think" it may be because of the thickness of the front cab support and the measurement is from top of frame to bottom of floor panel there. Not sure on the rear being only 3/4". What does your rear clearance measure? If you're at 3/4" and things line up correctly on the front clip, then it must be correct.

Left rear cab mounts measure LR 1.880 - RR 1.802 from the top of the frame to the floor panel with new mounts. Its gonna be a while before the from clip is in place.
FYI the front measured LF 1.927 - RR 1.917. From front to rear the cab is sitting almost level on the frame.

Red

Fellow Stovebolters; please know that I have Kevin's original door brackets from his rotisserie and as a rookie, I simply would have never made progress without them. I don't know why I won the lottery but I am thankful every day. If I can figure out how to post a picture on a "reply", I will include a picture. Kevin did an amazing job of calculating the center of mass of the cab and once a rotisserie is constructed around Kevin's door brackets, the cab spins like a top on the rotisserie. I intend to pass on my blessings (Kevin's door brackets) just as soon as I complete the cab repairs (I have been soooo slow). In the meantime, if me having the physical copy of the door brackets helps any of you create a repeatable spec, just let me know how I can help. Sincerely, Pat Gibney, Raleigh, NC

If you look it up in the Chevrolet Truck Repair manual, The specs are in there, and it tells you where to measure. The rear gap is real close to 3/4" , measured between the rear cab support bracket flange which is spot welded to the floor, and the frame.
I always put a piece of 3/4" board between the rear support bracket and the frame with the rear shackle mounts loosely bolted in place, then set the gaps at the front mounts and tighten the front mount bolts tight.
Then I go back to the rear mounts and set those gaps and tighten them up.
The reason being is that without the front mounts secured and shimmed correctly, the rear shackle mounts get wonky side to side, giving you false measurements.

When I measured from the support bracket flange to the frame its .81 & .79. Thanks for everyone's help.

Red