Granny or not to Granny T18A vs ???

[MMinMN]

Goal=Versatility, Weekend Warrior while crusing easily on the highway to and fro. while keeping the soon to be installed 401 as a powerplant

The T18A from all accounts appears to be one the best transmissions for off road work. The only issue is not having an overdrive gear to to an from those rock piles. ;-)

So what are the choices available that would maintain similar available low end gearing yet be as comfortable on the highway getting there(Yes I know the holy grail, I want it all )

Suggestions Iv'e read;
1) Replace the final drive ratios
Trouble with this idea is in order to get the highway comfort need, I think it would negatively impact the low end crawling ability the T18A is known for.

2) Replace with 3550/4500
Issues, not as low a first gear, new transfer case required, not has heavy duty.

3) Overdrive/Gear Splitting
Issues; I can't find one, do they exist? I do think this would be the best overall solution.

Thoughts from all this experience?

Thanks

[Dumpy]

If you wanna do good highway speeds, change the axle ratio. Crawl ratio won't be as low, but unless you wheel all the time in extremes I don't know how much the difference would be

[addicted]

If you want the ultimate in 5 speeds adapt an NV4500 to the 401. You could always find a Borg Warner R10 OD that bolts onto the back of the D20. It is 2wd only and running down the highway at speeds where you need the OD and the conditions require 4wd you shouldn't be running that fast anyway.

[joe]

(Yes I know the holy grail, I want it all )

Till they re-write the laws of physics that's gonna hang ya up.
There's always going to be a trade off, define your priorities and build accordingly and live with the downsides of the choosen option. There ain't no mega bad arse crawler that gets good gas mileage on the hwy unless it's on a trailer. Out of your 3 listed options 2.)NV4500 is prolly your best compromise or spring for one of those multi-geared aftermarket tcases.

[goldhammer]

Used to be an OD box you could put in front of the tranny, don't remember who made it or if still available, or what applications it was available for.

[Carnuck]

Ranger gear splitter. Still very much available.

[MMinMN]

Ranger gear splitter. Still very much available.

They dont' list one for the Jeep T18, they do list one for the Ford version. Unless I'm missing something

[MMinMN]

If you want the ultimate in 5 speeds adapt an NV4500 to the 401. You could always find a Borg Warner R10 OD that bolts onto the back of the D20. It is 2wd only and running down the highway at speeds where you need the OD and the conditions require 4wd you shouldn't be running that fast anyway.

As I snoop, that may be the only option left. Or the 370/6 speed perhaps seems to have the highest first gear.

[Carnuck]

They dont' list one for the Jeep T18, they do list one for the Ford version. Unless I'm missing something

I called them. Before I broke my shoulder I was going to send them measurements to replace the V8 trans spacer with on.

[MMinMN]

I called them. Before I broke my shoulder I was going to send them measurements to replace the V8 trans spacer with on.

Was that Advanced Adapter?

And they still make one for the Jeep T18?

Wow

[Carnuck]

Mine is a Ford T18 with the long input shaft

[MMinMN]

Mine is a Ford T18 with the long input shaft

With the AMC V8?

[addicted]

Here you go. http://www.greatlakes4x4.com/showthread.php?t=254725
That will make your problems a little cheaper to solve.

[Carnuck]

With the AMC V8?

Yes

[MMinMN]

Yes

Ok more details please? ;-)

Which bell housing?
Which Xfer did you use, the stock D20? or the D300?
Followed by Drive Shafts?

Were you happy with the outcome?