Ah your on the right path like me! HOw sweet would that be to have a 9" underneath? Man I can't wait. I thought hard about what to do instead of a W59 and I don't see anything as an attractive alternative. Seriously all manual Toyota transmissions have been broken under abuse. You just have to drive smooth and you'll never have a problem. When it comes to race cars and trucks if a transmission breaks they blame the driver, seriously. And I'm not talking about high end race transmissions or cars... all race cars.
This is also why most vehicles come with automatics - so they don't break and cost the mfg. money to replace under warranty. And they also throw skinny ass tires on vehicles for this reason too - so they break loose quickly and don't stress the drive train so much. When you strengthen one part the next part in line just breaks instead.
I would much rather replace a couple of W59s (if I ever have to) instead of spending 2 grand on a transmission and hope that it holds up.
The Toyota W59 transmission has a LOT going for it:
- It's very light
- They do take a beating well
- They are made for 4wd transfer case torque
- They fit the truck perfectly in terms of proportion
- You can find a hardly used W59 from a dismantling yard no problem
- They shift very well for a truck transmission
I really contemplated using the 6spd but I found a lot of complaints against the 1st and 6th gear having problems. So I just stopped thinking about it. But if I come across a Toyota 6spd 4wd tranny and t-case I'll probably scoop it up.
I did look into buying a 4L60E transmission. It's an automatic of course and they use them in pro trucks all over. You can buy a computer to control it for like $300 and they are awesome. BUT it's a monster! I know a friend that has one that's nearly new and it's all complete with the t-case and everything but it's just very very large. I could fit it but it just wouldn't be correct for a smaller truck with my smaller 1UZ. But if I'm putting in my rollcage and my friend decides to donate it I would make it work.
And of course there would go my fuel mileage if I put that in. : \