Well I am back, from the trip that is, 365 miles.

The tranny worked as advertised, it runs smooth, shifts well with a big "thud" but it is supposed to. Cruising at 80 mph it dropped the rmps just a bit over 500. Started the trip with a full tank as always and now I have about 1/8 more than usualy, so mileage is better. Exactly how much it is hard to say, but with the Tacoma trip coming up in just over a week, it will be close to 6k miles round trip including driving around there, I will monitor usage and have the results by mid November.

 

Thanks for the update.

 

Life is life and nothing is perfect.
Not even my new aux tranny install. Discovered small problem. The foront drive shaft, being longer now (the transfer case moved back about 12 inches, to allow the tranny to be bolted between the stock tranny and it) on a full extension of the suspension (like when you hit a large depresion in the road) touches the cross member that holds the tranny (stock) in place. The cross members has to be nothched a bit to accomodate this. No big deal except I do not have the time to have it donne. My trip to Tacoma has moved up two days, MY SON IS COMING HOME FROM IRAQ two days earlier. This week I have a lot of loose ends to tie up before I leave next Tuesday, and this work will need at least two days in the shop. So I am thinking the following: Is there any reason why I should not just remove the front drive shaft for this trip, I really do not expect needing 4 wheel drive, and have it all done right when I get back?
I appreciate any input. Thanks.

Peter

 

Here is the long term review:

I have driven the truck now just a bit over 7000 miles with the gear splitter installed. I do not have a single complaint. It works as advertised. I really like it. On the trip to Tacoma and back I was cruising with just a "tad" South of 85 mph. It felt like the truck was standing still, it was so smooth. The engine was running just under 2200 rpm. My gas mileage went up by about 1 mile per gal since the install, but pushinig it at mostly 80+, I was not expecting much of an improvement. Without it however I do not think I could cruise at 85-ish. The engine was reving at 2600+ and I was only goingunder 75. That is with 4.10 gears.
The main reason I bouth it was to drop the rpm at warp cruising.
For everyday driving I expect a much better mileage, since the engine will hardly "work" I use varp speed only for intergalactic travel.

My average was about 14.2 miles/gal before the install, and with the last fill up I averaged 17. 63. That is a considerable jump.
Either way, I do not think that it will pay for itself in gas savings anytime soon, but I love it just the same for the lower rpms, plus the convenience of still having the low gearing in case ever have to tow something heavy. That's about it.

 

Me too.
Most folks don't report much mpg gain.
Once you get over a certain mph it seems aerodynamics takes over and rpms don't mean as much.