‘39 Merc All Terrain Vehicle???

lurk

Junior Member
‘39 Merc All Terrain Vehicle???

Well, not really.

I’ve got a stock ‘39 Mercury sedan that I’ve been taking on camping trips this summer. Other than a few cooling issues that I’ve mostly got solved, I notice that climbing hills is tough on the old Merc. Paved or not, it seems to hate pulling up a decent incline (especially from a dead stop!)

I have a ‘59 GMC that’s 100% stock that wil damn near idle up a cliff side in granny low. I realize they are very different machines, but I’d kind of like it if the Merc was capable of something close to my GMC.

So, the question is this: what period (40’s era) upgrades can be done to the Merc to improve it’s hill climbing ability? The drivetrain is rock solid on the ‘39 and on highways and surface streets, I don’t have a single complaint.

Weird request, I know, but I’m interested to hear what you guys come up with.
 

Attachments

  • 59E7D3A6-DBFB-4AC1-B235-EA48540C3546.jpg
    59E7D3A6-DBFB-4AC1-B235-EA48540C3546.jpg
    50.7 KB · Views: 491
Re: ‘39 Merc All Terrain Vehicle???

You can gear it lower but hiway driving would suck.Get a running start on those hills.
 
Re: ‘39 Merc All Terrain Vehicle???

What kind of compression do you have on the merc?


What rearend do you have? 3.78?


Higher ratio will increase engine rpm and heat btw
 
Re: ‘39 Merc All Terrain Vehicle???

What kind of compression do you have on the merc?


What rearend do you have? 3.78?


Higher ratio will increase engine rpm and heat btw

Rear is 3.78. Compression is an even 90psi across all 8 cylinders. Low-ish compression, but the local flathead guys thought it was decent...

Also, i’m running 6.50x 16’s. I’m aware that a 6.00x 16 would help the situation slightly.

Car will currently do between 60-65 on the freeway, so like I said, I really can’t complain. Anyway, gonna slap a new Walker radiator in it next week and hit some hills.

It could just be that I just need more experience with it.
 
Re: ‘39 Merc All Terrain Vehicle???

369592

It is great that you are using your 1939 Mercury Town Sedan. I hope that you get the hill climbing issue sorted out?
 
Re: ‘39 Merc All Terrain Vehicle???

There were different first gear ratio transmission gear sets with lower first gear
 
Re: ‘39 Merc All Terrain Vehicle???

29 x 15 lower gear set will help in pulling away. 29 tooth cluster gear ,15 tooth main drive gear...........versus 28 x 16. Lots of 29 x 15's around.
Charlie ny
 
Re: ‘39 Merc All Terrain Vehicle???

There were different first gear ratio transmission gear sets with lower first gear


this is probably your best answer... call up mac van pelt and see what he has. I think I have one of the lowest sets available at the time. it's from a commercial truck that had the 4 cylinder so it's the super low first gear.


one other question is if you are at altitude during the hill climbing. you may be losing power that way??
 
Last edited:
Re: ‘39 Merc All Terrain Vehicle???

Marmon Herrington converted about any Ford vehicle requested to 4WD starting in 1936 or so. A conversion like that would be about as close as you would ever get to a 1959 GMC 4WD.

Those early Mercury cars had a different set up on ring & pinion than their Ford counterparts. The pinion was part of the drive shaft. This makes changing a ring & pinion set or even a complete rear axle a real chore. A new drive shaft set up has to be fabricated unless a person found an original set of 4.11 gears for a Merc.

A lot of Mercs had the 15/29 transmission gears in the early years of the marque but I'm not sure about the 1939.
 
Re: ‘39 Merc All Terrain Vehicle???

Before considering a gear swap in the trans, compare 2nd gear ratios. If you have to downshift to 2nd on a hiway grade, the lower ratio 1st gear also means a lower (slower) 2nd gear ratio, which may be too slow. What you need are more gears! A swap to a modern T-5 five speed would be ideal. It's a rather common swap; lots of info on this forum. A number of different gear ratios are available for this trans, too, from an extremely low first gear to an extreme overdrive and lots in between. Your car is already floor shift so that won't look much different. The period correct Columbia 2 speed rear axle will actually give you 6 speeds total,(a gear for every hill!).
 
Re: ‘39 Merc All Terrain Vehicle???

Also consider milling the heads to get the proper "quench", or "squish" dimension (head to piston clearance) as well as more compression. This will pep the old girl up noticeably.
 
Re: ‘39 Merc All Terrain Vehicle???

^^^ like this thinking right off if you want to just drive and enjoy how a 39 merc drives. Don't run it down.



Adding a little compression isn't going to hurt either.
 
Re: ‘39 Merc All Terrain Vehicle???

Also consider milling the heads to get the proper "quench", or "squish" dimension (head to piston clearance) as well as more compression. This will pep the old girl up noticeably.

Thanks for the input!





..and for the "take it easy, don't kill it crowd..."

I totally understand the sentiment that we should "drive carefully and enjoy.." these cars. There is certainly merit to that approach, but my brain rejects it as somehow demeaning to the engineering and strength designed into these vehicles.

I've had restored cars that are too nice to park in parking lots. I've had old cars that I updated with new technology like disc brakes and small blocks and I've had old cars with tired running gear that I was afraid to take certain places for fear of something breaking.

The point? I'm currently interested in old technology that performs at least as good as it did when new. These machines did great things in adverse situations back when they were new. There is no reason they can't accomplish the same tough tasks today.

Besides, if a trip to the hardware store is fun in an old car, imagine how fun a trip to an abandoned silver mine 25 miles up a ****** road would be!
 
Re: ‘39 Merc All Terrain Vehicle???

Marmon Herrington converted about any Ford vehicle requested to 4WD starting in 1936 or so. A conversion like that would be about as close as you would ever get to a 1959 GMC 4WD.

Those early Mercury cars had a different set up on ring & pinion than their Ford counterparts. The pinion was part of the drive shaft. This makes changing a ring & pinion set or even a complete rear axle a real chore. A new drive shaft set up has to be fabricated unless a person found an original set of 4.11 gears for a Merc.

A lot of Mercs had the 15/29 transmission gears in the early years of the marque but I'm not sure about the 1939.
I have 1938 literature that says Marmon-Herrington would charge all of $10 to fit 4.44:1 gears to any chassis delivered with anything else. My '47 runs 4.11's and a 1.5 ton truck 4-speed.



1947Mercury4x4_zps32a8dd23.jpg
[/URL][/IMG]
 
Re: ‘39 Merc All Terrain Vehicle???

From the historic information I've read on MH conversions, they liked to do the Fords better than the rest since they were easy to modify. They cut the axle bells on a standard Ford rear axle and installed their own constant velocity joint steering set up to make a front axle for 4WD conversions. They liked the 11-inch clutch and the T9 transmission too. It would be interesting to see what sort of transfer case they used on the light duty applications in the mid 30s and up to the war years. They made a lot of their own stuff for those conversions.
 
Re: ‘39 Merc All Terrain Vehicle???

The light-duty M-H transfer cases were single-range, either engaged full-time - with no shift lever - (the CV joints free-wheeled on curves), or could be shifted from that funtion (called "COMPENSATING") to locked into "POSITIVE DRIVE" (no freewheeling) for loose traction situations. In either case, the hubs stayed engaged.



 
Last edited:
Back
Top