Hilux92,
When you say "1st low with standard 2.28" are you referring to "1st gear in standard 2.28 low range"?
If so, then here is the ratio break down of a Single T/Case, one with 2.28:1 and one with 4.70:1, using a W56 transmission and 5.29:1 axle gearing:
| Gear | 2.28:1 | 4.70:1 Marlin Crawler |
| 1st (3.95:1) | 48:1 | 98:1 |
| 2nd (2.14:1) | 26:1 | 53:1 |
| 3rd (1.38:1) | 17:1 | 34:1 |
| 4th (1.00:1) | 12:1 | 25:1 |
| 5th (0.85:1) | 10:1 | 21.1 |
| rev (4.09:1) | 49:1 | 102:1 |
So as you can see, your current 1st gear will be like your new 2nd gear, your current 2nd gear will be like your new 4th gear, and your current 3rd gear is just a bit higher than your new 5th gear.
So to get a good idea of what 5th gear with 4.70:1 gears will feel like, shift your truck into 3rd Gear Low Range and see how that feels. That will basically be your new 5th gear.
Here are the speed comparisons with (true) 35" tires with the above setup up
held to 4500 RPM:
| Gear | 2.28:1 | 4.70:1 Marlin Crawler |
| 1st (3.95:1) | 10 MPH | 5 MPH |
| 2nd (2.14:1) | 18 | 9 |
| 3rd (1.38:1) | 28 | 14 |
| 4th (1.00:1) | 39 | 19 |
| 5th (0.85:1) | 47 | 22 |
| rev (4.09:1) | 10 | 5 |
(Calculations made with the Marlin Crawler Speed Calculator)So again, the same relationships exist, with the close approximation of your current 3rd gear acting as a slightly-faster new 5th gear.
I hope this answers your question.
The beauty of only replacing the gearing in a t/case is that there are no driveline or shifter modifications as required with dualcase setup.
The horrible thing about only replacing the gearing in a t/case is that once you engage low range, you will be stuck in Really-Really-Low-Range. You loose the factory range. This of course is
sustained in a dualcase setup as you can simply engage just one low range lever if desired.
I know there exist some sand and mud situations that would require speeds in excess of 20 MPH (32 KPH), but I find that in the snow, I always have the greatest success with my 4.70:1 low range in 2nd and 3rd gear with 37" tires. Works like a charm.
Regards,
BigMike
