[mosesburb]

Originally Posted by 1985-GMC

I'm building a suburban with a 97 12V, nv4500, 1 ton axles with 4:11 gears. For the kind of stuff you do on trails would a doubler helpful or would it be completely unnecessary. I'm just trying to decide if it's worth the extra trouble and money to do it now.

I didn't do much wheeling when I had the 4.10's in mine as that was when I was still dealing with the driveline vibration (which one attempt at a cure was a different rear axle that had 3.73's). That being said, I didn't like the 4.10's because they were too deep for a torque motor. Fine for a 350 or even a 454, but the Cummins would just wing up immediately then defuel and fall flat. With the 3.73's that problem was eliminated. The motor actually uses the torque it produces and feels much quicker now.

So, in my opinion, I don't think a doubler would help much with 4.10's for what I do. With 3.73's I would give a very cautious maybe. The ONLY time I wish I had deeper gears is when crawling through a rough spot in a trail or descending a steep grade, and then, only to control ground speed. I have never wanted for deeper gearing for more torque, ever. Now, I actually have a 203 range box built by ORD sitting here, setup for a NV4500 with the 32 spline input and the face drilled for the output housing of the 4500 that I decided not to install when I built the truck. So far I have not wished that I had installed it. I will however admit that I wish that I would have put either a 241 case or a LoMax 3.0:1 gearset in the 205 instead of the super terrible stock NP205 low range of 2:1. Once again, only for ground speed control, not torque multiplication. One other point on the multiple transfer case setups, I have heard of heat dissipation issues with the 203 range box as well as the low range units that use the 241 planetaries when used on the highway. Now not every unit, but more than a few have had issues.

So, if I had it to do again, I would still not put the doubler in, but I would definitely consider a transfer case with a low range closer to 3:1. Is the difference worth the pile of money needed to trade for one of these cases?? In the end, probably not....