The Stovebolt Site Forums The Shop Area Engine Shop Drivetrain advice wanted!!

Hello I am a newbie to this site and have a general question I was hoping someone here could shed a little light on for me. I am purchasing a 1941 Suburban that I plan on doing a complete frame off restoration on. It has the stock 216, 3 speed etc. I was also offered another 41 rolling chassis with a 235, open driveline and highway geared rear. Once the project is complete I plan on towing a prewar vintage travel trailer that weighs 2900 lbs in the summers. I would also like to have the advantage of an overdrive gear for daily use.
I have been going round and round in my mind as to what the best set up would be. Can I do it with a 235 or should I try to locate a 261? Should I try to go for a T5, or a 200r4 auto? What would the optimum rear end gear ratio be for hauling etc?
I really want to stick with an inline for this project.
Any advice or suggestions would be greatly appreciated at this point.
Thanks in advance!!
Johnny

Welcome to the 'bolt, Johnny; Interesting project you've got in mind. You'll probably get a lot of different opinions on this one.

Back in the good ol' days, my parents had a '50 Chevy with a 216 and we'd pull an old masonite trailer in places you wouldn't believe (Tioga pass, for one). The key was not to get impatient!

I think the 235 would be adequate, by the way is it a "full pressure" 235? I wouldn't want to use a babbit pounder for what you want to do. The T5 would be a good choice I think and a rear gear of 3:73 to 4:11 should work for you. The 235 can be tweaked here and there to give pretty good torque and the OD should get you down the highway pretty good when you're not pulling the trailer.

How fast do you want to pull that trailer? What hills do you want to climb.

If you are content running slower than most the traffic the 235 or 261 should be fine. For more power you could also look at a GMC 270 or 302, or maybe even a more modern Chevy 292.

I can't imagine being happy with a 235 pulling a trailer, but I like to run a little faster, at least with traffic.

A few years ago I caravaned with several others including a '57 Chevy wagon with a 235. Going across Idaho and Wyoming were speed limits are 70 and 75, the '57 Chevy limited our speed. It fell behind on the inclines and was not comfortable running that fast on the flat areas.

To put that in perspective, I was driving a 350 powered pickup and pulling another '57 Chevy on a dolly behind me. I was easily able to run the speed limit even uphill. The 235 powered wagon couldn't keep up.

Don't get me wrong, I'd love to own that wagon, but I'd never choose it to pull a trailer at highway speeds.

First off I want to say; thanks guys for taking a minute to respond. I want to ask questions before I start in hopes of wasting money and saving aggravation...so I really appreciate it.
I believe the 235 is a later full pressure oiler (I'll check it out on Thursday)
I would hope to be bale to reach speeds of 55 to 65 under load on semi hilly areas.
I like the idea of using the larger 261 because I could use the original motor mounts and if I decide to go for an auto the adaptor plate is available. I have located a GMC 270 but I was told that it is a slightly longer motor and I may have to alter the radiator placement plus my overdrive options appear to be limited... anyone have any input on this?
I like to go camping up in the CA Sierra mountians (because thats where the trout like to hang out) so I would like to be able to hill climb under load at speeds faster than 30 mph with which ever drivetrain I choose. I will probably do an average of about 1500 to 3500k miles a year towing the trailer.
Also any advice on a tranny? T5 or automatic?

sorry...I meant to say "in hopes of NOT wasting money"

Your overdrive options are the same weather you go with the chebby or the gmc motors as the bellhousings are interchangeable. It may be a little bit more tricky to find a flexplate for the 270, however.

I would pic the T5 over the automatic, but it isn't your only choice for an overdrive transmission. The A833 4 speed, and the NV4500 5 speed are adaptable to the chevy bellhousings.

The NV4500 gives the advantage of a granny gear to get the load rolling, and a .73 OD. It is a big and stout transmission that probably would not be needed in your application.

Another MUCH CHEAPER OPTION would be to use a 3 speed + overdrive transmission like the ones they used in the 50s.

The T-5 is probably the best performance for the buck. You will have to have an adapter plate made if you decide to use the '41 bellhousing. You may want to use that bellhousing because that is where the brake and clutch pedals mount. You could use a 47- 54 bellhousing that has been modified to accept the brake and clutch pedals, but then you would have to lengthen the splines and cut the snout of the T-5, so the use of a 1/2 inch thick adapter plate is actually a bonus.

I'm glad you're thinking inline. V-8s are boring. Yeah, I know they are better suited for the job if you want cheap, bolt on H.P., but everyone has one. Dare to be different. If you want to spend some money and get the best of both worlds, you can get a Gear Vendors O.D. They cost 3k+. When you combine it with an SM420, you get 7 forward gears. At least 6 that are practical. You can split 3rd and 4th for the hills, and use 4th over on the flats. You get the granny gear for uphill starts and pulling boats up a ramp, etc... and can go with a lower geared rear(I have 3:90), have good low end torque and still cruise at 70 - 75 on the highway. My 235 does fine pulling just over 1k pounds, but I don't think I'd be happy trying to pull much more. That's why I'm building a mildy hopped up 261 stroker. At some point, I want to pull a heavier camping trailer. I think the 261 will perform well. I'll let you know for sure next summer.
The 292 is also a good idea. I've used my neighbors 80s 3/4 ton with a 292 to pull my truck on a trailer about 60 miles and it was able to hold 65 on the hills. It's also low geared and would really kick butt if it had an O.D.
Last but not least, radials and GOOD brakes are essential for what you want to do.
Good luck!!!

Your transmission options are basically the same, running the Chevy six, GMC six, later Chevy six, or even most GM V-8's. The adapters to support putting modern automatics behind the earlier motors are not cheap, but they are out there.

My concern about the automatic in this case is the power the transmission will consume. You're choosing to limit power while pushing the demands on the drivetrain pretty far. A manual is going to allow more power to the ground.

The GM T-5 is a light duty transmission. While they seem to do fine in most inline applications and GM installed them in V-6 and 305 V-8 applications but did NOT in 350 V-8 applications. The reasoning is that the T-5 could not stand the additional torque.

The World Class T-5, which was used in Mustangs, is much tougher, but not an easy match to a GM bellhousing.

If you were not talking about a trailer I'd say the T-5 sounds like a good choice. Given that you want to pull a trailer I'd suggest looking at the A833 4 speed or the NV4500. They may be overkill, but the T-5 is marginal in a trailer pulling application.

Take your pick, risk failure or carry too much transmission.

Steve,
Good point about the trailer. I am always on the iffy side of the T5s. That is why I put a NV4500 in my 59, and plan to do the same in my 1940. Having actually gotten dirty and installed one I will have to say it is a big effen transmision that ways about 200 lbs and costs between $4 and $10/ lb. That is to say it is not cheap. I would absolutely reccomend this transmission for a built up inline engine that sees heavy towing or 4wd action. But it is a spendy option. You can get used NV4500s in the $600 range, rebuilt starting at $800 with a $300 core, or about $1800 for a brand new one. You will still have to get an adapter or a new bellhousing, cut the driveshaft or have a new one made, and callibrate the speedometer, which depends on weather you are using an electronic signal or a mechanical signal.

There is nothing better than a 5 speed with granny low and overdrive for towing save the Gear Splitter system that Macdaddy mentioned. With that system you have 8 forward gears, so you could virtually shift between the gears to find the engines sweet spot on any grade. By the way, it would also work on a NV4500 giving you 10 forward gears, but that may be overkill.

Anyway as mentioned there are many options for you. Decide weather you want auto or stick, and how much you want to spend, and we'll walk you through the pros and cons of it all. It can get expensive really quick.

Thanks for all the input!! I've checked out the NV4500 and it certianly looks tough enough. I also checked out and did some reading up on the Gear Vendors over/under drive units which also seem to be a good (but big dollar) option. I completely agree with you Steve, too much transmission is a better option!!..pretty at this point my attitude is that I dont mind spending extra money up front to ensure that I have something that will work.....in other words I'd rather pay for overkill than have to pay twice as much for underkill later.
A guy I work with suggested that I look into diesels for fuel economy and torque (he's an earthy type always preaching about biodeisel and healthy food) and after thinking about it I figured what the heck it's worth looking into. I have gone through three stovebolts, and had a plethora of V8's through out the years but have never dreamed installing a deisel!! But I do know that where they lack balls they have gain in torque... Any input on this?? In a 41 Suburban?? Am I crazy??
A side note here: and just for the record when I was a teenager and still in highschool I rebuilt a 54 235 blueflame six that I had in a Bel Air that ran like a top for 18 years, and took me all over hell and back with very little trouble, and to this day is still running strong. I wound up giving the car to a good friends son for his 21st birthday about five years back(.....and yes he takes really good care of her). That motor will always have a soft spot in my heart. Part of that is why I'm still leaning towards a six for the Burb.....but I am ultimatley looking for the most practical set-up for the application; decent fuel economy for a daily driver and good enough torque to tow a 2900lb trailer at highway speeds.
Anyone ever fooled round with deisels?

I saw some pics of a diesel powered decco burb from one of the car shows. It has been done. As soon as you mention the "D" word one name pops in mind, and that would be Grigg Mullens, a member here that is doing, or has done a diesel swap in one of his stovebolts.

I wonder if that cummins turbo diesel would drop under that hood. Might be able to get one pretty reasonble out of a wrecked dodge, may even get the NV4500 with it.

Cool!! I want to thank everyone for all of the great input. I posted under the big bolt section asking about the diesel option and Grigg sent me a link to a Cummins 4BT swap forum. Amazing!! I never would have imagined that anything like that existed. This forum alone has shown me that I need to wake up and join the rest of the 21st century. I used to make fun of my friends (and thier kids) who would spend hours online instead of doing something "more productive" .....but I must say that after all of the suggestions I got on here its got me reading into all kinds of stuff I wouldnt have thought of on my own....and it's lots easier than writing down advice from guys at car shows and swap meets and researching it from manuals etc. later....which (if not going stock) is how I've pretty much done it before.
So thanks for taking the time. I've got plenty of good info here and have been looking into your suggestions....as of now I'm leaning towards a 270 or a 292 with the NV4500...but am still going to research the diesel idea just to research it.....but as of now, in my mind there is still nothing sexy about a diesel.......but I've learned in life to never say never.
All the best!!
Johnny

The GMC 302 stright six would be the perfect motor for you and pulls up hills and trailers.It is the best stright six i ever driven and i have all of them.But a stright diesel would be sweet as well.I plan on building a truck with a duramax diesel v-8 soon as possable.I have a 2005 duramax diesel truck and i love it.Hope it helps.

I don't know from experience, but a local man who is known here as Buffalo sez the 302 can't be beat in the inline world. He has racing experience with inlines and claims that they make the 302 race against themselves at Bonneville as they are in a class by themselves.
As I've said on previous posts, my dream project is a 30s GMC pickup hotrod with the 302, a WC 5speed and Corvette suspension and brakes. Of course I would race it.
If I were to use it more for towing, I would want more of a truck chassis w/the setup I have now (SM420 w/ Gear Vendors O.D.) I'm going with the 261 on my Chevy because it's a well preserved truck that I believe should remain looking stock. (The 261 was an option in 62 and is a bolt-in swap and it will look almost identical to my current stock 235). If it were a total rebuild/rodstoration I would go with the 302.

I feel the same way. But if you want to tow something heavy at speed its worth thinking about.

My co-worker with a new Duramax dually gets about 12 mpg carrying a camper and pulling a horse trailer. My 454 powered 1-ton four-wheel-drive pickup pulling a load never does better than 8 mpg and has done less than 6 mpg.

If I ran that truck more than a few thousand miles a year I'd be tempted to go Diesel. Last time I ran the numbers best case if I towed with it 28,000 miles annually I'd save $10,000 a year on fuel. That would acually be enough to make the payments on a new one.

Since my actual usage is about one-tenth of that the potential savings haven't changed my mind. You might want to think through what those numbers would be in your case. Starting from scratch the Diesel option could start to make lots of sense.

As unpopular as the idea is with many, I'd probably run a V-8 if I were building a truck to tow a trailer. Oh, wait a minute, I'm doing just that... I'm putting a Cadillac 500 in a 1-ton '54 GMC to replace the old Chevy 4x4.

I like the sound of a big V-8 working hard.