Looking for some insight, especially from those who have installed and run the Mark's gears, as to which ratio would be a better fit for my intended needs/usage.
Slowly building a D50 with a D4BF(4D56t) turbo diesel / V5MT1 5MT / 4.636 diffs / 235/85r16AT (+/-32") to be used primarily as an overland, dirtbike/firewood/logging road hauler, bad winter weather, and general go anywhere truck.
While rock crawling isn't typically on the menu, I'd like the increased security of a substantial low range crawl ratio to reduce the overall strain on the rest of the drivetrain/suspension/truck in tough situations, aid in navigating steep/rough/primitive roads/tracks in deep mud and snow, and in instances when the truck is heavily loaded.
I recently tracked down a V5MT1 w/Super Select transfer case from a '95 Gen 2 5MT and in addition to rebuilding the transmission, plan to order and fit Marks4WD gears, the question is do I go 2.7 or 3.15?
2.7 Gears (Gen 2/5MT) - https://www.marks4wd.com/paj-gen2-2-7m.html
3.15 Gears (Gen 2/5MT) - https://www.marks4wd.com/paj-gen2-3-15m.html
The general consensus seems to be that 3.15 gears are the way to go, but the vast majority of those who run them are into more significant crawling than I intend to undertake, and do so with 4ATs; Aisin R4AW3s (1st: 2.804, 2nd: 1.531, 3rd: 1.000, & 4th: 0.754).
Factoring for the same 4.636 diff gearing I'll be running, a 4AT would yield the following crawl ratios:
2.7 Gears = +/- 35:1 (2.804 * 4.636 * 2.7)
3.15 Gears = +/- 41:1 (2.804 * 4.636 * 3.15)
However, since I'm running a V5MT1 5MT, my 1st gear will be much lower (1st: 3.918, 2nd: 2.261, 3rd: 1.395, 4th: 1.00, & 5th: 0.829), resulting in the following crawl ratios:
2.7 Gears = +/- 49:1 (3.918 * 4.636 * 2.7)
3.15 Gears = +/- 57:1 (3.918 * 4.636 * 3.15)
While, I'm pretty confident the 4.636 diffs will fit my needs, there's a remote chance I may end up with 4.90 gears if I ever increased the tires to say a 285/75R16 (+/-33") at some point down the road, such a change would yield the following crawl ratios:
2.7 Gears = +/- 52:1 (3.918 * 4.9 * 2.7)
3.15 Gears = +/- 60:1 (3.918 * 4.9 * 3.15)
The 3.15 gears just seem too low and slow for anything I realistically intend to do, in light of that, I'm leaning heavily toward the 2.7 gears.
It seems they'll be more than adequate for my needs, particularly with the diesel's low end torque, and will require less modification to fit, avoiding many of the issues reported with installing the 3.15 gears in 5MT transfer cases:
Can anyone more knowledgeable than myself think of anything I've missed, haven't considered, or offer any first hand experience?
Thanks!
Slowly building a D50 with a D4BF(4D56t) turbo diesel / V5MT1 5MT / 4.636 diffs / 235/85r16AT (+/-32") to be used primarily as an overland, dirtbike/firewood/logging road hauler, bad winter weather, and general go anywhere truck.
While rock crawling isn't typically on the menu, I'd like the increased security of a substantial low range crawl ratio to reduce the overall strain on the rest of the drivetrain/suspension/truck in tough situations, aid in navigating steep/rough/primitive roads/tracks in deep mud and snow, and in instances when the truck is heavily loaded.
I recently tracked down a V5MT1 w/Super Select transfer case from a '95 Gen 2 5MT and in addition to rebuilding the transmission, plan to order and fit Marks4WD gears, the question is do I go 2.7 or 3.15?
2.7 Gears (Gen 2/5MT) - https://www.marks4wd.com/paj-gen2-2-7m.html
3.15 Gears (Gen 2/5MT) - https://www.marks4wd.com/paj-gen2-3-15m.html
The general consensus seems to be that 3.15 gears are the way to go, but the vast majority of those who run them are into more significant crawling than I intend to undertake, and do so with 4ATs; Aisin R4AW3s (1st: 2.804, 2nd: 1.531, 3rd: 1.000, & 4th: 0.754).
Factoring for the same 4.636 diff gearing I'll be running, a 4AT would yield the following crawl ratios:
2.7 Gears = +/- 35:1 (2.804 * 4.636 * 2.7)
3.15 Gears = +/- 41:1 (2.804 * 4.636 * 3.15)
However, since I'm running a V5MT1 5MT, my 1st gear will be much lower (1st: 3.918, 2nd: 2.261, 3rd: 1.395, 4th: 1.00, & 5th: 0.829), resulting in the following crawl ratios:
2.7 Gears = +/- 49:1 (3.918 * 4.636 * 2.7)
3.15 Gears = +/- 57:1 (3.918 * 4.636 * 3.15)
While, I'm pretty confident the 4.636 diffs will fit my needs, there's a remote chance I may end up with 4.90 gears if I ever increased the tires to say a 285/75R16 (+/-33") at some point down the road, such a change would yield the following crawl ratios:
2.7 Gears = +/- 52:1 (3.918 * 4.9 * 2.7)
3.15 Gears = +/- 60:1 (3.918 * 4.9 * 3.15)
The 3.15 gears just seem too low and slow for anything I realistically intend to do, in light of that, I'm leaning heavily toward the 2.7 gears.
It seems they'll be more than adequate for my needs, particularly with the diesel's low end torque, and will require less modification to fit, avoiding many of the issues reported with installing the 3.15 gears in 5MT transfer cases:
Gen 2 Transfer Case 3.15:1 Gear Swap
Angelo, Its not too bad , but its a 16% drop off compared to the 3.14. It is still better than standard. But at $1400 its looking less attractive every day. Not knocking Hardmans here because he was the only one who stepped up to the plate to help us guys out which was fantastic, &...
4x4wire.com
Can anyone more knowledgeable than myself think of anything I've missed, haven't considered, or offer any first hand experience?
Thanks!
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