Frequently Asked Questions

Frequently Asked Questions

I am considering upgrading to 9.00 x 20 tires.  I hear this will gear me up.  What do you think?

VOV: Yes, it will gear you up, but depending on where you live and what engine you have, it may not do you much good.  The engineers of the ’40s where not fools – they matched the tire size to the truck and it’s needs.  The 9:00 x20’s are less expensive, and will gear you up which are pluses if you live in a level area, and/or have a larger engine in the truck.  The down side is that you will be shifting that much more on hills and will lose any speed advantage they may give you on the level.  One other thought – these trucks were NOT MADE to go 60 mph.  I have heard stories of people altering them to do that, but the brakes, steering and other systems are simply unsafe at much over 45mph.

Should I put silicone fluid in my brake system?

VOV:   First, I can tell you that White Post and many other brake rebuild houses strongly recommend NOT to use it.  It may be incompatible with some of the gaskets.  As I was told by another restorer “your vehicle went 50 years with DOT 3 in it and has not had the care and maintenance you will give it now that it has been restored.  If it goes another 50 years, won’t you be happy?”  If you change the fluid every few years, it will not build up moisture to any great degree, and the system will last for decades.  Silicone has it’s attributes, but it also can be a nightmare if those tiny leaks in your new system cause it to get on your new paint job.  There are few products that do a good job of getting silicone off well enough for new paint to stick as it should.

I need to rebuild my Chevy engine.  Should I go with the original or later model 235?

VOV:   You will find parts and rebuild kits much more readily available for the later model 235’s.  You will also end up with a better engine with full pressure oil and insert bearings.

Can I put another engine in my Chevy other than the 235?

VOV:   Yes.  The easiest engine to install is the Chevy 261.  It will bolt right in with no modifications.  The GMC 270 from the CCKW will also go in but modifications will need to be done due to its length.  I have seen enough conversions to know that just about anything CAN be done – it is just a question of your time, money and talent and what you want out of it when you are done.

I have a GMC and can get a Chevy door for my closed cab.  Will it fit?  What other parts interchange?

VOV:   The Chevy door and the closed cab GMC doors are the same.  Here are some other parts that interchange:

Doors – Chevy/GMC closed cab same
Windshields – Chevy/GMC closed cab same
Headlight buckets – Chevy/GMC same
Wheels & tires – Chevy/GMC same
Mud flaps – Chevy/GMC same
Wheel Cylinders and Brake shoes – Chevy/GMC banjo axles same Split axles use same brake parts EXCEPT front wheel cylinders

Fenders:   same.

Should I buy new wheel brake cylinders or buy rebuilt cylinders?

VOV:   Either will work just fine and there is usually not a huge difference in price.  There are advantages to the rebuilds though.  First, it is done to tighter tolerances and sleeved with brass or stainless steel (ours use SS) so it won’t be susceptible to corrosion down the road.  You will also have the right cylinders particularly in the front where you need the correct angle on the connection.

Can I mount a different style hydrovac on my truck?

VOV:   Yes.  Although it is desirable to keep the original, rebuild costs on these are very high (generally well in excess of $450).  Good NOS ones are occasionally available and are the more economically feasible.  Remember there were 3 variants of the GMC Hydrovac just during the war and then several others post war.  Obviously these frequently got interchanged based on availability.  You may have to modify the mounting bracket, but as long as they have the capacity to handle the truck, they will work fine.

I want to build my own troop seats/racks.  How can I do it?

VOV: The slates are usually made of oak, but since they are painted OD, nearly any hardwood will work.  The slates are 1″ x 2 3/4“;  The sides are 107 3/4″  and the front is 71″ across at the top.  The area for the rear window is cut out by having the slats either side of it being only 22” long. Used hardware is available or you can buy a newer set for say an M-35, remove the wood and cut/re-drill to fit or replace the wood with your own. There are a few small differences but not significant. The stakes from an M35 or M211 are made of square tubing and have a blade that hooks the front corners together. The original WWII stakes were made by taking a flat piece of sheet metal and bending it in four places then overleaping the ends and spot welding them.  The front corners were connected by a pin that slid into the loop this pin was welded to the front right stake.

Uprights for the top bows are 7/8″ x 25/16″ x 45″ although the height may vary.  These are the same for GMC and Chevy.