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Hi all, I'm Richard, a new member and I was told this is the place to go for advice on modifications.

Here's what I've gotten myself into. My wife just purchased a 1942 3/4-ton pickup. (I'll try to attach some pictures.)

She has given me an objective to make this thing run like a modern truck without it looking any different than it does now. Here's what I'm starting with:

The truck is in great shape with a frame-off restoration (5 years ago). The engine and trans were swapped sometime in the past to an early, but recently rebuilt-to-stock 350 w/Turbo-350 auto transmission. The rest is mostly original, including the 6-lug artillery wheels. The brakes are also original, but had a booster added at some point and stops okay for a truck. The truck spent its entire life in California until last week and is surprisingly solid.

Here's what we want to get to......

It needs to be a safe and reliable regular driver, including interstate trips. It should have impressive power and speed. And very important that it must still appear stock/original.

Can it be done? Just brain storming a bit, here's what I came up with:

Power steering (wife insist)
Front disk brakes (safety)
New Crate Engine (EFI and fuel injection) and new automatic transmission (I'm thinking around 450HP with similar torque...suggestions, opinions???)
Front suspension/steering improvements
Heater
Air Conditioning because we live in South Carolina (Does Vintage Air have a recommend kit? Anyone else?)
Do I need a different rear axle? Suspension? Diff?

What else should I consider...or not consider. I'm not concerned about cost so much as making sure things are done right with respected and proven components that will last.

Thanks, I appreciate all the help I can get.

Rich B.

Thanks for coming to the HiPo Shop where we talk hotrods. Your goals are reachable for sure. You can use the search function of this site to do research on each component you are contemplating. There are reputable companies out there with “Kits” to accomplish all of your wife’s wishes. You have already reached two major milestones. Bought the truck and your wife is on board! Your half way there. The truck is absolutely beautiful as is and you are going to experience some push back from some here on doing further modifications. Ignore them and do whatever makes your wife happy. Happy wife happy life.

Thanks for the warm welcome!

I feel the same about modifying a nice truck, like this. So I'm hoping our modifications will not prevent taking her back to stock. Also, other than the engine and transmission, (which I will sell), all parts will be cleaned, properly treated, and stored in a conditioned environment.

What you want, wife wants, is a common mod called a Restomod. The look of old with new chassis components. So my opinions, suggestions and questions are next.
1. Who is going to do the work? You or a shop? I see you are an engineer and gear head. That's good. Many of us here are Gear heads and engineers, shop instructors, experienced builders, DIY specialists and fabricators.
2. An early, but recently rebuilt 350, is perfectly good. A 350TH is good, a 700r4 would supply overdrive for "interstate trips" and a easy swap. Don't need a bigger motor.
3. Everything you want is available in kits, donors, rebuilt/new FLAPS and aftermarket Classic Truck vendors.
4. I would start with the front axle: disc brakes and PS. Tapered roller bearings or a whole new/donor axle that would have it all.
5. You say "everything else is original and ask for rear end suggestions. You can't possible have a 350 motor with an original 42 rear....could you???????? Could be, the axle is full float and strong. But 4.55 ratio!!!!!!!!!!!!!!!!
6. You are in a "IFFY" area, I always recommend keeping the frame and adding axles and restomod components instead of an aftermarket preloaded frame or donor, but I don't know how hefty the 3/4 frame. My guess is it is overbuilt for the era and will be OK. The GM heritage site will give dimensions and thickness of frame channel. So you can check that and I will also. Another factor I would have to consider is what all was added, modified, cut off, compromised of the 42 frame by PO's.
7. I would keep the leaf spring design front and back. It's a truck and will not ride like a car. The leaf spring system allows for much, much easier axle swaps. I, myself don't favor Mustang'ish, Fat Man'ish, clips and etc.
8. Placing an aftermarket preloaded frame under the body or donor will seem like cool and easy do. But will have a whole new set of issues.
9. It's hard to advise without see the whole undercarriage and all the surprises you forgot to tell us or haven't seen.
10. There will be members here who have done this stuff to a 40's truck. I have only done it to 55.2-59 trucks. Fairly similar though. Take all of the Blog Sites and How-To info with a grain of salt as you search for info.
11. The production of civilian trucks during a WAR year would be very low. Your truck is pretty rare and in great condition.
12. Your Vin may disclose which of the two available 3/4 models you have. The numbers on your rear axle and other parts can be of help if keeping any of it. Those components you are swapping will be sellable.

VERY IMPORTANT
Make a list or a drawing of all dimensions.
1. WMS front and rear
2. Frame width
3. Ride height
4. Wheel base
5. Radiator to fire wall
6. Take many measurements and pics of "AS IS" truck chassis/motor/trans/mounts/axles/steering/gas tank....for future ref. Some of the measurements/specs will be in the GM Heritage Documents online.

1942 3/4 T has ladder frame with 5 Structural Crossmembers, Frame build from 42K psi cold rolled steel. C Channel is 5 27/32 tall, legs are 2 1/4, thickness 3/16. Strong enough.
Due to being a 3/4 T, the suspension and axles are strong. Stiffer ride than 1/2T (comment is for original suspensions)

A sf 14 bolt axle for the rear has 6 lug bolts but is a good modern axle to use, have to check width.

Ed

Nice looking truck. Did your better half give you a time line on getting all these mods completed? I'll be watching this thread.

She's PURDY... All of the things you suggested are doable with time and money. Being that it's not original as it sets now you shouldn't have the pain of trying to decide if you should modify it further.
I fall into the straight axel category, I just couldn't bring myself to cut the frame. The ride and height can be soften up with some easy mods, power steering and power disc brakes are a common modification so the knowledge is there. From the look of your truck I personally would hate to hack it up. But as we say "It's your truck", either way the folks here will jump in and give a hand.

THANKS!!!!!

1. Yes I'm an engineer (mechanical, electrical minor), a proud gear head, and worked as an industrial mechanic, and also at a body shop painting cars to help pay for college. I have a nicely equipped 40'x30' garage shop (not a parking garage) with 14' lift, welders, air, tools, etc., and am in the process of completing a replica roadster I built from ground up. Other than alignments and mounting tires, there's not much we can't do here. I'm retired, have the time, and budget isn't a significant issue (yet, LOL). Unfortunately, I'm not familiar with these trucks or what is available. So I'm happy having a shop or an independent do the work if it doesn't become a part time long term effort. My preference is to learn while I assist someone who knows what they are doing. Second is letting a shop do it all, third is doing it without assistance by myself. Once I know what I'm doing, I'll want to do all I can by myself.

2. Thanks, and I completely agree on the transmission. This transmission is the Turbo-350 with a lock. So it "sort of" has a 4th gear, but not really. The engine runs surprisingly well considering that the carburetor looks like it's never been rebuilt and the choke was never connected. I'm sure the engine is fine, but not impressed with the installations' attention to detail. I haven't done a pressure test or taken fluid samples on it yet, though. However, I've seen no oil or fluid leaks. Good news!

3. Excellent! I was hoping that these were available.

4. I agree and our priorities align exactly. A built up new front axle is the most efficient way to go.

5. The rear end "looks" original. I have no issues in replacing that either. I need to get under it and take some more pictures and videos and have added a couple here. I'll try to get some more and post them here later this morning.

6. Great advice. Thanks! The frame looks good and solid, so it stays. Not sure about any PO changes to it, I'll check that out when I get more pictures.

7. Agreed and this is good news. I wanted to do this and also keep any welding to a minimum.

8. Agreed and we're thinking very much alike.

9. Understood.

10. Will do.

11. Thanks. Once the mechanical stuff is done, we'll have a classics shop go over the paint and body for touch up and cut and polish. She seems very solid. Having spent its entire life in California was good for it.

12. The VIN is 6BM081285. I've learned that "6" designates the Oakland California plant, the "BM" is for a 3/4 ton, and "081285" may or may not be an engine number. The title shows it first sold in 1942, but no month is listed. Outside of that, I am told what the previous owner was told. And I'd like to know more and verify it's history. For any original parts removed, they will absolutely not be trashed. I may keep them, or more likely make sure they get to someone who needs them for an all original build.

Thanks again for going through all the effort to help out. Your input is greatly appreciated.

Rich B,

#5...... The differential pictured is not original. Looks to be from late 50s early 60s. I’m not an expert so the real gurus will chime in soon.

From a quick look the axles I'm not sure that's the original rear axle. Comparing it to my '41 3/4 ton. Mine has a plug in the rear cover to check oil level. Can't see it in the photo but there's also a couple bolts that locate/hold the pinion bearings in place. Your rear has been converted to tubular shocks. The springs have been modified, my springs are mounted on top of the axle where yours are under. Mine is the lighter duty 3/4 ton and has 7 main springs and 6 overload springs where yours has 2 leaves total. Your front springs appear close to original. I'm not a suspension expert but I would suspect you have very different spring rates front to rear. First easy check to do would be to check the gear ratio, should be 4.557 if original..

If the differential is 6 lug, I'm guessing late 60's, 70's 1/2 ton 12 bolt.
Looks like quite a few leaf springs have been removed, probably to soften the ride.

Also, it appears that the stock rear engine mount/crossmember has been completely cut out. Some reinforcement in that area may be prudent as that crossmember
tied the frame rails together at the front spring rear shackles.

Neat truck !

Yes a nice "modern" truck 12 bolt differential. Very good. Does look like a crossmember was cut off. This crossmember is near the rear spring mount. Possible stress problem without that. Frame needs checked for cracks in that area Normal universal tubular aftermarket motor and trans crossmembers/mounts have been used.
The 42 3/4 was available as a "regular" or with HDE (Heavy Duty Equipment). This was designated as BM. So your VIN is 6=Oakland, BM= HDE, 08= August 1942 and 1285 is a sequential build number for the Oakland plant starting at 1001.
HDE gave 17" wheels, larger brakes and heavy duty rear springs. 8 leaf.

Front suspension/axle does look original. If disc and bearing kits are available for 42 3/4, that would be the ticket. Indications are that this will be sourcing a issue.

As said, your rear springs are highly modified. Spring under axle. 2 leaves. This would have a lowering affect. Better ride.

All of the proposed mods to a restomod can be done by you at home. Nothing to be afraid of. I am a retired Mechanical Design Engineer (aerospace) also. Good to see you on here.

Thanks for the head's up and info. I also saw the missing cross member. And a bit more crawling under it this morning. Most is just stuff that could happen to any truck over an 80 year span. But some things just get a direct toss into a SMH basket.

I don't like the way brake lines are run. They are completely operational, but sloppily installed with a number of "hand" bends in hidden areas, and they are not as dressed and clamped along the body as I'd like, and a number of other things that were just done sloppy on the mechanical side.

Other things go right to the "WTF" file. Like the missing cross member. And the transmission support is "Unimpressive" both in design and execution. The good news is that I won't hurt anything of significant originality by modernizing a few things. We planned on some major expenses to make it a reliable daily driver.

On the good side of moving along on things, I spoke with my engine builder (same race shop that built the engine for my little racer) and he's putting a turnkey package together for me. As bartamos suggested, we're focusing in on a 350 based engine with a 700r4. I gave him a budget and told him to "make it pretty." LOL. Now to order new front and rear ends that will work with the 15" artillery wheels.

Not sure there is anything "wrong" with the rear differential, except maybe the gear ratio.
Should hold up well to the 350/auto combo.

"Now to order new front and rear ends that will work with the 15" artillery wheels."

Yes, 68ironhead, I'm confused also. The front and rear end are OK and have the wheels on them. The only issue I see is disc front, which is nice but not mandatory. If I am not mistaken, the front drums and shoes and cylinders are big, if original. Big sq inch.(HDE). Must be some 41-47.1 owners here who have figured a way to do disc on front.

Sorry about any confusion, guys...I sometimes brain storm while I'm writing.

My thoughts on replacing working equipment.

The truck is destined for daily and interstate use, so I want the diff. gear ratios to better match the intended purpose, including comfortable use and operation at interstate speeds. The existing system is rather inefficient all things considered. So that's where replacing the rear diff comes from. As long as I'm doing that we "might as well" add in disks, new springs, bushings, springs, hardware, shocks and etc. because......"might as well."

Up front, it looks like I can use a '47 rack and pinion kit power steering kit, however that doesn't resolve the front disks issue. The bushings look shot and things have to come apart for that anyway. So, by the time I replace all the bushings, bearings, springs and hardware, I "might as well" just toss in a complete new system.

So now, I'm in the "might-as-well" realm. Has it ever happened to you? It's happened to me so often I could be a guide. So, at 60 (and soon 61) my experience tells me it's best to give the "might-as-well" Gremlins some leeway and hear them out. In the long run it's usually cheaper and you have fewer regrets...all within reason, of course.

My 2 cents worth.....
Like the built 350 / 700R4 combo. If you are prone to stomping on it once in a while, would be nice to have posi in the rear end.
You should have decent RPM at highway speeds


Pull the front axle and install - gasp - Mustang 2 style, with power rack. Gets you good suspension, fairly large disc brakes, power steering, and lowered ride height.
There are a number of AC systems out there with small condensers. Still a tight fit under 42 dash, but doable
Consider tilt steering column as stock seats have minimal adjustments

Beyond that only limits are your imagination and your pocketbook

First, what your wife wants is IMPOSSIBLE. If 1940's rides could be made to ride, handle, and stop like modern ones they would still be being made new. She is not the first one with this DREAM as we have had to crush the hopes of many. My suggestion is to find a similar truck at a show in your area and ask the owner if he would take her for a drive. Offer a brew or meal for reward. If nothing else come to Trenton, Texas and I can line her up with rides ranging from basic restomod to $100k show ones. Our rides since 1976 have won everything from local shows to a Great 8 award at the Detroit Auto Show so you are hearing from 54 years of experience. Post note: we STILL screw up on a regular basis but it doesn't cost the customer as we figure it as a tax on idiots that never had the sense to find a real job.

A basic IFS, discs, 350 engine, od trans, 9" Ford rear, that is 15 years old on resto in these pics:
[img]https://i.postimg.cc/N2kTgLFg/Trigger-005.jpg[/img]

[img]https://i.postimg.cc/xcjgXS2s/Trigger-007.jpg[/img]

Note weathered bed wood and worn through running board coating that proves age:
[img]https://i.postimg.cc/c6P4HdwW/Trigger-003.jpg[/img]
[img]https://i.postimg.cc/rK9bHJ8H/Trigger-013.jpg[/img]

A high dollar mod that still does not ride, drive or stop like a new truck even with a 20k Detroit Speed chassis:
[img]https://i.postimg.cc/mzRpVzv4/Stude-Justin-s-40-Cougar-Cat-004.jpg[/img]

Evan, you are off the rails, This is not like you. Of course she can have a restomod. The true restomod is a modern chassis with a classic restored original looking truck or car body, exterior and interior. Sometimes with an extra flair or two. The "mod" in restomod means modern......as in modern. The original body will stop, turn, handle, ride and accelerate on it's modern undercarriage/drivetrain components.
We don't know exactly want she wants, your negative comments are curious.
We have been advising to leave some of the chassis as is because we think that is a good enough restomod, but the poster and wife may decide to go full hog. You can put a car ride under that body if you want.

P.S. Rich or his wife never said anything about ride. Mostly safety, reliability and handling.

Thanks for the comment, and I agree.

From an engineering perspective, it's very doable and I believe we are realistic in our goals. We do not need this to ride like a Mercedes, or handle like a Vette. But we do want it to behave more like a modern truck with modern reliability.

Driving it around for about 20 miles yesterday wasn't encouraging for the suspension, but the truck runs fine. It goes where I point it, stops when I tell it too and isn't leaking all over everything. In all it's a great little truck for being nearly 80 years old. Heck, it's a great little truck. If we were only doing weekend rides, having coffee or towing it somewhere, I'd clean up the engine and let her be.

However, relative to our goals, there are a few more issues. The steering linkages are a tad loose when moving but less than I expected. However, there's a strong side to side front wheel shake or "shimmy" over 45 and a lot of lean when cornering. The ride is overly harsh and jarring (needs more spring and less shock I think?) My tractor isn't that rough on me and it doesn't have a suspension. LOL. The brakes work well at slower speeds, but not so much when braking quickly at higher speeds. It's not "dangerous" but there is some quick fade.

I'll be digging into it more tomorrow.

Thanks again!

I guess I did rant a bit but there are ones that come in insisting on a 2021 Lexus traits on an old ride. They just flat don't believe it can't be done. On the 46 and older ones with the roll out windshield and windlace instead of weatherstripping wind noise makes radios and conversation disappear above 65mph. My point was to not make an old/new comparison or disappointment will follow. Of course engine, trans, brakes, body roll, handling, and creature comforts can be vastly improved but still not remotely on par with the computed designed and wind tunnel tested new ones. The old look, new performance has it's limits and as long as one is aware and accepts this there is no problem but some don't and therein lies a problem for builders.

Evan, understood.

"It's actually possible to make a silk purse from a sow's ear- - - - -but it makes the pig look funny, and it doesn't hear very well!" Dealing with customers with unrealistic expectations isn't just limited to the hotrod building business- - - - - -gunsmiths , construction companies, and a few other service industries seem to have the same sort of problems!
Jerry

Evan, I completely agree. I'm an Engineer and understand the limitations of design. (Math works, more people should try it. LOL)

And they'll give you the "Thousand questions of why not" treatment.

My "train driver" brother, the one with a Master's degree in EE and a PhD in plasma physics, has a favorite saying- - - - -"Constants aren't- - - - -variables won't!"
LOL
Jerry