Opinions/experiences with the "typefour" ZF mod

[jaluhn83]

Couple thoughts:

1) Why do you want a wide ratio? The close ratio trans matched the diesel power band pretty well with stock gears. Even with the close range I don't like the gap between several of the gears. (partially because of the quirky way my turbo system works) All a wide range is really going to get you is a deeper 1st which you really shouldn't need with a 4.10 and stock tires. If you do need super low range just put the t-case in low.....

2) There's no such thing as an over/under GV or US Gear unit. It's either over/direct or under/direct. You could get them setup either way, but it's not a overdrive/underdrive in one box. The brownie box is the only aux trans that can give you a true over/direct/under.

3) The GV unit is really not designed for splitting gears. It's designed to add an extra top gear. You probably *can* split with it as long as you're going fast enough (over 30-40 mph) but that's really not what it's supposed to be used for. Remember that the more you shift it and the more load it's under the more you'll wear the clutches.....

 

[icanfixall]

When I choose too I use my gv in all the forward gears. Just around 20 or 25 mph these units make enough hydraulic pressure to shift fine. I start in 1st. Then run it up to 25 mph and shift in the gv. Then run that till I can shift into 2nd and at the same time out of the gv. So now I'm in 2nd. Then shift in the gv. I do this all the way till I have the rpm and road speed I feel is the best for what I'm hauling. I can get 8 forward gears. I can't underdrive 1st. I have to be running before I build pressure. With 3.55 gears its sometimes a tuff pull from a dead stop. Thats why I want a set of 3.73 or 4.10 gears out back.. RLDSL has 15 forward gears with his brownie trans behind the ZF5 speed and 3 reverse gears.. Thats the best choice of gears anyone could want..