Info needed: Building a repro LRDG 1940 Chev.

[Mike K]

This is a interesting pic. What size are the wheels on this 41 model ?

53257575_2367705179920605_6432069312260866048_o.jpg

[Bob Carriere]

Hi Tony

Very hard to tell but I would say a CMP rim with some adapter to bolt on to the truck's original bolt pattern.

It would seem that using c15 4x2 axles would be the easiest .....but alas....they are very hard to find.

One option is to have wheels made using a brand new rims and a flat centre piece drilled for the GM 10 holes.....quick fast and$400 each

Second option would be to fabricate a flat adapter from 3/8 steel plate that will bolt to the original GM 10 bolts leaving room for the second set of 8 holes for the CMP pattern .Having available CMP rim much cheaper.

Replace the front beam axles with a Ford tubular front axle which will take regular CMP rims......and a regular C15a rear axle again compatible to the CMP rim. Cheaper rims are avialable any 900x16 would fit.... and a lot sturdier construction using parts we are familiar with.

With the above the rear axle would be slightly offset to the right but not critical I hope.

[Hanno Spoelstra]

Bob, I’m sure the sturdy Ford front axle would not mind bearing the Chevrolet ;-)

But bear in mind that that axle was designed to replace a driven front axle, so the chassis sits higher. It is a straight tube and not a dropped I-beam. So on a 4x2 Chev the front would be raised higher than the rear. Or are planning on building a “Gasser” hot rod?

When the snow melts I would go out with a tape measure and measure up all the various axles you have. And flip out the parts lists. Maybe some brake drums or entire spindles can be swapped. Did you ask Rick about how his truck was converted? It seems the French guy cracked the code on the wheel-drum combination.

If the conversion is too complicated, I would opt for an 8-bolt CMP rim and drum combination, it will look the part. Only the real anoraks will note you would not be using 10-bolt rims. But those guys will find other things to nitpick on your repro! Just build the truck you’re dreaming of, I’m sure it will be awesome.

HTH,
Hanno

[Bob Carriere]

That is one of the many issues ..... most of which I could address or work around them BUT..... everything is covered with that cold hard stuff for at least another 6 weeks.......

So far the wheels can be converted to a "look a like" by welding a 3/8 flat piece of steel to the back side of a current 16 in. CMP wheel..... then drill out the heart at 4.75 in and the necessary 10 bolt holes........

But the front axle track is much wider than the dual wheel rear axle when only one tire is used...... a solid steel or aluminum spacer????

We will get it done..............

[Bob Phillips]

Just a couple of comments..
the photo referenced by Tony is exactly the same as what I have with one difference, if you look closely at the far wheel you can see that there is an extra support from the bottom of the axle out to support the bottom of an extended king pin. This means 3 points of support for the king pin. The one I parted with is like the photo. I had it running in a 15cwt for a couple of years. The one I have left is the same but without the bottom support. Thed axle is a hollow tube. It would be very easy to cut and weld it wider or narrower as required. I also have access to some 2- 3 ton commercial Ford rear axles if that would be of any help. Changing track width with spacers is a common soluition also, I had 2x M139 bridge trucks (5 ton) that had heavy spacers on the front axle each adding about3 inches to the width of the tires. ( still have some if you have a 5 ton)
BP

[Bob Carriere]

Hi Bob.... Hi everyone....

Finally found a picture of the tubular axle....... tell me if that is the same.

The width of the axle...tracking width....according to reference manual matches other CMP tracks standardized at 70 to 71 inches..... and since I may have to use a CMP C15a rear axle to facilitate using existing CMP rims it may ntobe an issue.

If need be removing and re-fabricating the spring perches is not impossible.... in my days we torched them off and rewelded new one made from thick wall square tubing..... a lot will depend on how standard the 1940 frame width is?

Bigger issue raise by Tony....... the current axle has a 6 inch drop the ambulance axle is straight..... which would raise the nose unless I fabricate spacers for the rear axle......

Too early for that..... I need to get rid of the snow and get my hands dirty touching and measuring.

Still working on a wooden mock up adapter to allow using CMP rims with the existing 1940 axle........ but rather fascinated with the tubular axle.

Bob do you have one axle and possibly a second one???? will "parlez" a price or a donation to MLU upkeep on your behalf...... not sure I need to consider the Ford beam front axle at this point but will look them up in Grant's bibles-s-s-s-s.

Found a wheel fabricator, of all places Canada South of Montreal and not in California, who also has some interesting options for a modern any width and diam rim with a solid flat steel center drilled to the GM 10 bolts.

...and it gets complicated.... got a parts book for the 1940 Chevrolet and another for the Maple Leaf 1940....... and they show 4 different Beam axles and 4 different wheel/rim offset which creates a multitude of front axle width.

Bob....look for a PM.....

Cheers

[Bob Phillips]

Hi Bob see my PM
photos are the heavy version of the axle- was just thinking there is a Maple Leaf GM truck at my local yard with a drop front axle- hubs from the CMP straight axle may fit right on....can investigate if it ever warms up
BP