Help with new trans options

[JuttyShabango]

Guys,

The 3speed sucks...what are my options? How much better is the 4speed? Do I need a new trans case with the 4speed? will it adapt to my GM Small Block with the same adapter as the 3speed?

Ugh...overload of info here...

 

[phishtaco]

While I'm no mechanic.....but since you have a SBC, you would probably go with an SM465 tranny, I think woody still has plates available to connect to yout tcase.

Or to stay Toyota..H41 4sp. with low first gear or H42(like mine) usa 4sp.....either one you would need to buy some parts to adapt to the 3sp tcase. 3sp. tcase has lower gears when compared to the 4sp.

 

[phishtaco]

http://www.root45.com/SM465Orion/Gears.htm

good chart break down

 

[phishtaco]

Oh and 1 more thing....If you really want an H42, I'll buy an H41 we can put that in my truck and you can have mine

 

[JuttyShabango]

http://www.novak-adapt.com/knowledge/sm465.htm

Thanks Marty...gonna marinate on this for a bit. I would like to keep the yota tcase but may consider a used Atlas in there also...not sure yet.

I have the rear offset axle out back...not sure what to do with it yet either..This is going to have to be a winter project...me thinks..

 

[zebrabeefj40]

SM465 or SM420 are the two easiest/cheapest swaps for lower gears. If you get a 10 spline version of either trans and a plate adapter you're good to go. Whether you need a different bell housing or not depends on what you already have and what trans you're going to (I'd bet you have an SM420 bell with a plate adapter there now). I have at least one extra cast iron bell housing for a Chevy available if you end up needing one. Have to measure it and see what trans it's for though (I think for SM420 also). After that you'll need to get the driveshafts lengthened/shortened. Both these transmissions work great with a V8.

To go to a Toyota 4-sp requires a few far more expensive parts; specifically a adapter bell housing. $400-500 used is the going rate IIRC. Given the cost vs. benefits of a Toyota trans vs. a SM420/465 I'd recommend the SM4xx trans. Unless you get a non-USA Toy 4-sp or 5-sp (H41-4 sp/H55f-5 sp both have a 5:1 First gear) it's hardly worth the effort. I've seen complete SM420/3-sp T-case set-ups go for the cost of the adapter bell alone.

The other common option is an NV4500. Not quite as low as an SM4xx series trans but lower than either of the Toyota options plus it has an overdrive for the highway. It's also kinda pricey but there are a few more benefits compared to the other options...

I'd also recommend sticking with the stock rear axle for the time being. They're pretty stout as is. They can easily run a 35" tire if you're not too hard on the throttle (pinions are the "weak link" but you'll note that Woody runs stock stuff on his Cruiser). I'd also recommend running the truck in a fairly mild form (IE hold off on the lockers and big lift) and learn how to drive it. They will go FAR once you learn how to drive them.

HTH,
Nick

 

[JuttyShabango]

SM465 or SM420 are the two easiest/cheapest swaps for lower gears. If you get a 10 spline version of either trans and a plate adapter you're good to go. Whether you need a different bell housing or not depends on what you already have and what trans you're going to (I'd bet you have an SM420 bell with a plate adapter there now). I have at least one extra cast iron bell housing for a Chevy available if you end up needing one. Have to measure it and see what trans it's for though (I think for SM420 also). After that you'll need to get the driveshafts lengthened/shortened. Both these transmissions work great with a V8.

To go to a Toyota 4-sp requires a few far more expensive parts; specifically a adapter bell housing. $400-500 used is the going rate IIRC. Given the cost vs. benefits of a Toyota trans vs. a SM420/465 I'd recommend the SM4xx trans. Unless you get a non-USA Toy 4-sp or 5-sp (H41-4 sp/H55f-5 sp both have a 5:1 First gear) it's hardly worth the effort. I've seen complete SM420/3-sp T-case set-ups go for the cost of the adapter bell alone.

The other common option is an NV4500. Not quite as low as an SM4xx series trans but lower than either of the Toyota options plus it has an overdrive for the highway. It's also kinda pricey but there are a few more benefits compared to the other options...

I'd also recommend sticking with the stock rear axle for the time being. They're pretty stout as is. They can easily run a 35" tire if you're not too hard on the throttle (pinions are the "weak link" but you'll note that Woody runs stock stuff on his Cruiser). I'd also recommend running the truck in a fairly mild form (IE hold off on the lockers and big lift) and learn how to drive it. They will go FAR once you learn how to drive them.

HTH,
Nick

Nick,

Thank you for taking the time to spell that out. In a Nutshell too! I do need to learn how to drive this thing for sure and will slowly take my time learning the ins and outs. This became very clear after unloading it Day One. Totally differnet than Minis.

Good news on the stock axle set up cause I like it honestly. This doesn't need to be a hardcore offroader, but rather a well built trail rig/DD.

Have decided it will remain spring under for a long time. It's already tall enuff and don't want to sacrifice it's drivability for ground clearance I'll never need.

One thing is for sure...Cruzas are as much fun as I imagined and owning one is even better.

 

[FJ40Jim]

Mark,
I have an SM420 you can have cheap. 420 has the lowest first gear, but is more crude in street driving. OTOH, w/ a 383 stroker, you've got the torque to pull just about any gearset.

The 420 adapts to the stock J30 case very easily w/ a common plate adapter.

The 420 may bolt to the BH in the truck now, depends on how hillbilly the swap was.

Obviously, there is some HB factor when a truck has a 400HP engine and no brakes and a non syncro'ed 3speed tranny.

 

[JuttyShabango]

Mark,
I have an SM420 you can have cheap. 420 has the lowest first gear, but is more crude in street driving. OTOH, w/ a 383 stroker, you've got the torque to pull just about any gearset.

The 420 adapts to the stock J30 case very easily w/ a common plate adapter.

The 420 may bolt to the BH in the truck now, depends on how hillbilly the swap was.

Obviously, there is some HB factor when a truck has a 400HP engine and no brakes and a non syncro'ed 3speed tranny.

It was owned by military so imagine some things were limited as far as access. The plate looks like AA quality from the bellhousing to the trans. My thoughts after talking to Karl were to get the overdrive out of a 4500 with the .75 final drive. Crawling isn't important so the SM series offers no help with the final drive ratio the same as what I got

The motor is balls...flat out and reliable. Been daily driving it and just got back from a 100 mile round trip. Fix the trans issue and it's a nice daily.

400 hp is a stretch for now, thinking more like 250-275 is more accurate but with a vortec head, tbi, and a serpentine setup then pushin that much might be a reality....but no way I'd be fawkin' gay enuff to dyno the bitch...

These things are totally different than mini's and runnas' but the principles are the same..at right now and growing

 

[FJ40Jim]

To increase final drive ratio, use fine spline 3.70 diffs and 35" tires. Top speed will be 167MPH @6000RPM in that configuration, without need of an OD tranny. Cruise speed is 2300rpm @65MPH.

 

[JuttyShabango]

To increase final drive ratio, use fine spline 3.70 diffs and 35" tires. Top speed will be 167MPH @6000RPM in that configuration, without need of an OD tranny. Cruise speed is 2300rpm @65MPH.

That's not a bad idea then get the gear reduction in a new case.. It would be nice to be able to cruise like you outlined and still be able to get my slow on at around 70:1