The Ford Barn

lurk · 08-07-2018, 06:27 PM

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.

texas webb · 08-07-2018, 10:36 PM

You can gear it lower but hiway driving would suck.Get a running start on those hills.

Tinker · 08-07-2018, 10:40 PM

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

40 Deluxe · 08-07-2018, 10:51 PM

A period correct solution would be the Columbia 2 speed rear axle.

lurk · 08-08-2018, 02:35 AM

Quote:

Originally Posted by Tinker

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.

mercman from oz · 08-08-2018, 03:59 AM

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It is great that you are using your 1939 Mercury Town Sedan. I hope that you get the hill climbing issue sorted out?

Kurt in NJ · 08-08-2018, 07:18 AM

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

Charlie ny · 08-08-2018, 08:05 AM

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

revkev6 · 08-08-2018, 08:08 AM

Quote:

Originally Posted by Kurt in NJ

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??

rotorwrench · 08-08-2018, 08:44 AM

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.

Automotive Stud · 08-08-2018, 09:29 AM

Have the factory heads shaved for higher compression will help.

40 Deluxe · 08-08-2018, 02:56 PM

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!).

40 Deluxe · 08-08-2018, 03:06 PM

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.

Vintage Copper 47 · 08-08-2018, 10:23 PM

Just drive it.. very carefully.. and enjoy...

Tinker · 08-08-2018, 10:32 PM

^^^ 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.

lurk · 08-09-2018, 12:12 AM

Quote:

Originally Posted by 40 Deluxe

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 shitty road would be!

jagnweiner · 08-09-2018, 07:13 AM

Somehow, I'm reminded of the classic scene from "It's a Mad, Mad, Mad, Mad World" featuring Phil Silvers and a 1948 Ford Convertible. :-) See attached at 0:28 and again around 1:21. https://www.youtube.com/watch?v=HhaPZagxWpM

mh_merc · 08-09-2018, 10:08 AM

Quote:

Originally Posted by rotorwrench

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.

[IMG]

[/IMG]

rotorwrench · 08-09-2018, 10:58 AM

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.

mh_merc · 08-09-2018, 11:10 AM

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.

mh_merc · 08-09-2018, 11:54 AM

[QUOTE

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.
[/QUOTE]
Here's an example of how Marmon-Herrington did it:

[IMG]

[/IMG]

lurk · 08-09-2018, 05:41 PM

Quote:

Originally Posted by mh_merc

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.

Woah. I had no idea such a creature existed. Super neat.

rotorwrench · 08-09-2018, 05:53 PM

From what I understand, the transfer case has an early version compensator drive unit that allows the front axle to slip free of the drive system. More modern set ups are like a differential to a certain degree but those set ups were more like a detroit locker by comparison. When you turn sharply while it's shifted into compensating drive, it starts slipping like a rachet does. It makes a noise that sort of sounds that way but it allows one unit to rotate at a different rpm than the other. As long as you drive relatively straight, it makes no noise. They may have made noise but they did function OK.

Tinker · 08-09-2018, 10:13 PM

Quote:

Originally Posted by mh_merc

[/IMG]

Man this is sooo great! Love it.

Love the 40's merc grills too. Had a ford 42 sedan with a similar grill. Very nice vehicle!

Tinker · 08-09-2018, 10:18 PM

Too the op poster. Drive it, post pictures, and enjoy.

Mart · 08-10-2018, 04:57 AM

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Old Henry drives his late 40s Ford over all sorts of unpaved roads. His car is all stock and has good reliability, except for possibly tyre problems.

There are lots of videos on youtube.

Mart.

mh_merc · 08-11-2018, 02:22 PM

Quote:

Originally Posted by lurk

Woah. I had no idea such a creature existed. Super neat.

So is your '39!

mh_merc · 08-11-2018, 02:29 PM

Quote:

Originally Posted by Tinker

Man this is sooo great! Love it.

Love the 40's merc grills too. Had a ford 42 sedan with a similar grill. Very nice vehicle!

THANKS! My first woodie was a '42. A M-H clone was made a few years ago, but unfortunately was lost in one of those terrible fires in Calif. last year.

[IMG]

[/IMG]

mh_merc · 08-11-2018, 02:44 PM

Quote:

Originally Posted by rotorwrench

From what I understand, the transfer case has an early version compensator drive unit that allows the front axle to slip free of the drive system. More modern set ups are like a differential to a certain degree but those set ups were more like a detroit locker by comparison. When you turn sharply while it's shifted into compensating drive, it starts slipping like a rachet does. It makes a noise that sort of sounds that way but it allows one unit to rotate at a different rpm than the other. As long as you drive relatively straight, it makes no noise. They may have made noise but they did function OK.

I can't comment on the driving characteristics in COMPENSATING DRIVE; it was apparently removed from my t-case to prevent wear (it did bind, skip and complain in POSITIVE DRIVE the one time I tested it on dry pavement). Here's how M-H explained it:

tgarner317 · 08-11-2018, 05:11 PM

Interesting thread!

rotorwrench · 08-11-2018, 06:11 PM

Thanks for that MH information MH Merc. I figured that drive compensator set up would look something like that. It has the dogs for direct and the rachet for a free wheeling affect. Sprag clutch technology was just starting to show up when the Lincoln cars got those first overdrive transmissions but that was a simpler way to deal with the problem at the time. Those CV joints were way ahead of there time. Most front wheel drive cars use the same technology now.

mh_merc · 08-11-2018, 09:17 PM

Cool stuff, huh? I've had my Merc over 28 years - it's been really fun collecting and learning about M-H history.

Brendan · 08-11-2018, 11:44 PM

Quote:

Originally Posted by Kurt in NJ

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

yes a pickup had a lower first and second gear.with my 36 pickup first gear was just to get it moving, and second you could do 25 mph. that was with a 411. now i have a 39 trans with taller first and second gear

Brendan · 08-11-2018, 11:52 PM

Quote:

Originally Posted by mh_merc

THANKS! My first woodie was a '42. A M-H clone was made a few years ago, but unfortunately was lost in one of those terrible fires in Calif. last year.

[IMG]

[/IMG]

i have seen your car, it sure was beautiful, sorry that you lost it

Mart · 08-12-2018, 02:41 AM

I remembered the constant velocity joint is referred to as a Rzeppa joint. intrigued by the history I googled it and it turns out Harry Rzeppa was a Ford employee and patented the design in 1926 or 1927.

Mart.

mh_merc · 08-12-2018, 09:12 AM

Quote:

Originally Posted by Brendan

i have seen your car, it sure was beautiful, sorry that you lost it

Thanks, but that one wasn't mine - just comparing Ford and Merc differences. My old '42 still lives back east somewhere.

Bored&Stroked · 08-12-2018, 10:27 AM

Back to the original question: Some performance upgrades to the engine would surely help - with more compression (tighter head to piston quench) being the easiest one to do.

If I'm correct, the 39-40 Mercury had a somewhat unique rear-end situation - with a solid/integral drive shaft and pinion (like a Model A). Changing the rear-end ratio would require a whole new Mercury only driveshaft/pinion and ring gear setup. I don't see this as an option.

A Columbia will not help your situation at all (it will provide over-drive ratios) - if just used with what you already have.

Another solution would be to change the rear end to a 4.11 or 4.44 rear ratio with the more "normal" Ford style ring and pinion - which would help your hill climbs, but make highway cruising speeds lower. I'm not sure if a 4.11/4.44 set of Ford gears could be used with the Mercury banjo (anybody know?). Then you'd need to cut/customize the original Merc driveshaft to have a "coupler" like the Fords used.

On top of the above, then you could add a Columbia setup - to give you "highway gears" in addition to your hill climb gears. These rear ends were the best original style solution in that everything works with your current chassis/frame/transmission setup.

The downside of the 4.11/4.44 plus Columbia deal is that there is a lot of time and expense involved . . . Columbia rears (correctly rebuilt) are not cheap by any means.

Good luck - glad to see you out there having fun with your ole' Merc . . . cool as Hell what you're up too!

B&S

jimTN · 08-13-2018, 04:19 PM

Are you sure the rear end is a 3:78? A lot of the Mercs came with 3:54 rears which would make it difficult on the hills. I have a 32 with 18" rubber, stock 85 (35) and a 3:78 that will climb hills very well and easily run 65 mph. I have Columbia's in my later stock flathead cars with 4:11 gears that will climb any mountain around here.

08-07-2018, 10:36 PM	#2
texas webb Senior Member Join Date: Dec 2010 Location: San Antonio Texas Posts: 636	Re: ‘39 Merc All Terrain Vehicle??? You can gear it lower but hiway driving would suck.Get a running start on those hills.

08-07-2018, 10:40 PM	#3
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	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

08-07-2018, 10:51 PM	#4
40 Deluxe Senior Member Join Date: May 2010 Location: now Kuna, Idaho Posts: 3,779	Re: ‘39 Merc All Terrain Vehicle??? A period correct solution would be the Columbia 2 speed rear axle.

08-08-2018, 03:59 AM	#6
mercman from oz Senior Member Join Date: May 2012 Location: Queensland, Australia Posts: 10,372	Re: ‘39 Merc All Terrain Vehicle??? Sponsored Links (Register now to hide all advertisements) It is great that you are using your 1939 Mercury Town Sedan. I hope that you get the hill climbing issue sorted out?

08-08-2018, 07:18 AM	#7
Kurt in NJ Senior Member Join Date: May 2010 Location: on the Littlefield Posts: 6,159	Re: ‘39 Merc All Terrain Vehicle??? There were different first gear ratio transmission gear sets with lower first gear

08-08-2018, 08:05 AM	#8
Charlie ny BANNED Join Date: May 2010 Posts: 3,019	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

08-08-2018, 08:44 AM	#10
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,436	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.

08-08-2018, 09:29 AM	#11
Automotive Stud Senior Member Join Date: May 2010 Location: New Jersey Posts: 832	Re: ‘39 Merc All Terrain Vehicle??? Have the factory heads shaved for higher compression will help.

08-08-2018, 02:56 PM	#12
40 Deluxe Senior Member Join Date: May 2010 Location: now Kuna, Idaho Posts: 3,779	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!).

08-08-2018, 03:06 PM	#13
40 Deluxe Senior Member Join Date: May 2010 Location: now Kuna, Idaho Posts: 3,779	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.

08-08-2018, 10:23 PM	#14
Vintage Copper 47 Senior Member Join Date: Mar 2017 Location: The sleepy San Fernando Valley Posts: 394	Re: ‘39 Merc All Terrain Vehicle??? Just drive it.. very carefully.. and enjoy... __________________ WALT "We sleep safe in our beds because rough men stand ready in the night to visit violence on those who would do us harm". "Old enough for the experience & too young to know better"

08-08-2018, 10:32 PM	#15
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	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.

08-09-2018, 07:13 AM	#17
jagnweiner Senior Member Join Date: Sep 2016 Location: Geneseo, IL Posts: 290	Re: ‘39 Merc All Terrain Vehicle??? Somehow, I'm reminded of the classic scene from "It's a Mad, Mad, Mad, Mad World" featuring Phil Silvers and a 1948 Ford Convertible. :-) See attached at 0:28 and again around 1:21. https://www.youtube.com/watch?v=HhaPZagxWpM __________________ Regards, Scott '47 Mercury Convertible '25 Dodge Bros. Touring Car '63 MG Midget

08-09-2018, 10:58 AM	#19
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,436	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.

08-09-2018, 11:10 AM	#20
mh_merc Member Join Date: Dec 2017 Posts: 32	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 by mh_merc; 08-09-2018 at 11:29 AM.

08-09-2018, 11:54 AM	#21
mh_merc Member Join Date: Dec 2017 Posts: 32	Re: ‘39 Merc All Terrain Vehicle??? [QUOTE 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. [/QUOTE] Here's an example of how Marmon-Herrington did it: [IMG][/IMG]

08-09-2018, 05:53 PM	#23
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,436	Re: ‘39 Merc All Terrain Vehicle??? From what I understand, the transfer case has an early version compensator drive unit that allows the front axle to slip free of the drive system. More modern set ups are like a differential to a certain degree but those set ups were more like a detroit locker by comparison. When you turn sharply while it's shifted into compensating drive, it starts slipping like a rachet does. It makes a noise that sort of sounds that way but it allows one unit to rotate at a different rpm than the other. As long as you drive relatively straight, it makes no noise. They may have made noise but they did function OK.

08-09-2018, 10:18 PM	#25
Tinker Senior Member Join Date: May 2010 Location: MN Posts: 7,053	Re: ‘39 Merc All Terrain Vehicle??? Too the op poster. Drive it, post pictures, and enjoy.

08-10-2018, 04:57 AM	#26
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,754	Re: ‘39 Merc All Terrain Vehicle??? Sponsored Links (Register now to hide all advertisements) Old Henry drives his late 40s Ford over all sorts of unpaved roads. His car is all stock and has good reliability, except for possibly tyre problems. There are lots of videos on youtube. Mart.

08-11-2018, 05:11 PM	#30
tgarner317 Member Join Date: Apr 2014 Location: Los Osos, CA Posts: 83	Re: ‘39 Merc All Terrain Vehicle??? Interesting thread! __________________ -Troy Zephaniah 3:17

08-11-2018, 06:11 PM	#31
rotorwrench Senior Member Join Date: Jun 2010 Location: San Antonio, Texas Posts: 16,436	Re: ‘39 Merc All Terrain Vehicle??? Thanks for that MH information MH Merc. I figured that drive compensator set up would look something like that. It has the dogs for direct and the rachet for a free wheeling affect. Sprag clutch technology was just starting to show up when the Lincoln cars got those first overdrive transmissions but that was a simpler way to deal with the problem at the time. Those CV joints were way ahead of there time. Most front wheel drive cars use the same technology now.

08-11-2018, 09:17 PM	#32
mh_merc Member Join Date: Dec 2017 Posts: 32	Re: ‘39 Merc All Terrain Vehicle??? Cool stuff, huh? I've had my Merc over 28 years - it's been really fun collecting and learning about M-H history.

08-12-2018, 02:41 AM	#35
Mart Senior Member Join Date: May 2010 Location: Solihull, England. Posts: 8,754	Re: ‘39 Merc All Terrain Vehicle??? I remembered the constant velocity joint is referred to as a Rzeppa joint. intrigued by the history I googled it and it turns out Harry Rzeppa was a Ford employee and patented the design in 1926 or 1927. Mart.

08-12-2018, 10:27 AM	#37
Bored&Stroked Senior Member Join Date: Jan 2011 Location: Central Ohio Posts: 5,067	Re: ‘39 Merc All Terrain Vehicle??? Back to the original question: Some performance upgrades to the engine would surely help - with more compression (tighter head to piston quench) being the easiest one to do. If I'm correct, the 39-40 Mercury had a somewhat unique rear-end situation - with a solid/integral drive shaft and pinion (like a Model A). Changing the rear-end ratio would require a whole new Mercury only driveshaft/pinion and ring gear setup. I don't see this as an option. A Columbia will not help your situation at all (it will provide over-drive ratios) - if just used with what you already have. Another solution would be to change the rear end to a 4.11 or 4.44 rear ratio with the more "normal" Ford style ring and pinion - which would help your hill climbs, but make highway cruising speeds lower. I'm not sure if a 4.11/4.44 set of Ford gears could be used with the Mercury banjo (anybody know?). Then you'd need to cut/customize the original Merc driveshaft to have a "coupler" like the Fords used. On top of the above, then you could add a Columbia setup - to give you "highway gears" in addition to your hill climb gears. These rear ends were the best original style solution in that everything works with your current chassis/frame/transmission setup. The downside of the 4.11/4.44 plus Columbia deal is that there is a lot of time and expense involved . . . Columbia rears (correctly rebuilt) are not cheap by any means. Good luck - glad to see you out there having fun with your ole' Merc . . . cool as Hell what you're up too! B&S

08-13-2018, 04:19 PM	#38
jimTN Senior Member Join Date: May 2010 Location: Powell, TN Posts: 2,509	Re: ‘39 Merc All Terrain Vehicle??? Are you sure the rear end is a 3:78? A lot of the Mercs came with 3:54 rears which would make it difficult on the hills. I have a 32 with 18" rubber, stock 85 (35) and a 3:78 that will climb hills very well and easily run 65 mph. I have Columbia's in my later stock flathead cars with 4:11 gears that will climb any mountain around here.