Ok, I'll admit that I don't know much about auto tranny's. Here's your chance to show everybody what you know.

I'm thinking of putting an auto tranny behind my 4.3 V6 along with a Dana 300 in my Buggy.

Questions are:
1) What do you think would be a good tranny?
2) What about torque converters? I've seen some different stall speeds and stuff, what's good for rock crawling?
3) Any other words of wisdom?

Again, I know how they basically work, but haven't had any experience with auto tranny's in a performance situation.

I currently have a Toyota 5 speed and toyota Dual cases.

700-R4! Obvious choice. :D Good low 1st gear (3. something to 1) and overdrive. Wire in a switch to lock up the converter (stocker works fine depending on engine mods) when you want it locked. And mount a damn good cooler for it. :flipoff2:
Don't know if the 300 was ever behind a 700 so make your own adapter if you have to!

If you are driving this on the street everyday I would use the 700r4 for the reasons above, but if this is mostly a trail rig I would think about a turbo 400 (which you can get a low frist gear added). Converter, I would stay with stock or a low stall.

I run an auto in my jeep with 4.88 r/p ,4 to 1 xcase and a stock converter on 35"and it climbs like hell on the rocks.

for a 4.3 you should go with a th350. short, cheap, and easy to find. get one that had a np208 t-case behind it and all you need to do it get an adapter input shat for the d300 as the adapter plate will work. i run an atlas (same bolt pattern as a d300) behind my th400 that came with a np208 case. all i had to do was redrill one hole and all the rest lines up.

Originally posted by kid
If you are driving this on the street everyday I would use the 700r4 for the reasons above, but if this is mostly a trail rig I would think about a turbo 400 (which you can get a low frist gear added). Converter, I would stay with stock or a low stall.

I run an auto in my jeep with 4.88 r/p ,4 to 1 xcase and a stock converter on 35"and it climbs like hell on the rocks.

unless you get a hell of a deal (like a modded 700 r4 for cheaper than a 400) I would say go 400

think of this a school bus lives all its life with a 7 somthing rear end and a 3 speed and goes 60 - 70 when is your buggy gonna see that kinda speed and for how many miles...


now with that said....tranny guys - is it posible to use a selectable lockup switch that will work at any RPM but have a unlocked stall speed of say 1200 - 1300 rpm??

now with that said....tranny guys - is it posible to use a selectable lockup switch that will work at any RPM but have a unlocked stall speed of say 1200 - 1300 rpm?? [/B][/QUOTE]


I checked into this already for my rig, was told I could do it but would loose the multiplication form the conveter.

go with a th350, 203/ d300 . Insted of gettin an adapter, spend the money on the 203 doubler

In the last Peterson's 4WOR they showed bolt-on bellhousings that would allow you to cut back an AT housing and bolt it up to virtually anything. So, if you wanted to run a 727/300 or something else unusual behind your 4.3 it's no problem. A solution in search of a problem, IMO.

For your buggy I would go either 400 or 350 with a 1200 and under stall converter. For t case , I think a yota case with 4.7
gears or keep the dual set up if ya got the room! Also, run as
large of a cooler as you can find with an dedicated electric fan for
it.

yeah keep the doubler. if you go auto and stock dana 300 you will want lower gears soon. I think the toy cases are as strong as the 4 to 1 dana 300 and cheaper to replace if you break one. Plus you have them. I would go TH350. I don't think you want to lock up a 700r4 converter except under the specific conditions that the stock setup locks it up. I don't think the lockup clutch mechanism is up to the task. Yes the 700r4 can be built super strong and has a lower first gear, but it is not low enough to work good with a 2.6 to 1 transfer case and once you go 4 to 1 the TH350 is low enough. Like mentioned above the biggest cooler you can get is good and a temp gauge. make sure that the valve body you use makes it stay in first gear when you put it in first, and will not let it shift to second on a down hill. most stock valve bodies are not like this. On the converter get a stock one from a vehicle with a 350 this will produce a slightly lower stall speed than the one that came with the 4.3. You don't want to go too low or it will seem totally guttless and pull hard on the brakes when you are trying to stay still. You should use a later model stock converter. people talk about the torque multiplication of a torque converter being 2.4 to 2.8. Basicly that is the efficiency of the fins. A long time ago they were just flat blades, now they are carefully designed airfoils, because the auto manufactureers need to post good gas mileage numbers. you can spend over a grand on a well designed and built aftermarket converter that has properly designed and built fins, or you can get a cheap one that has stamped steel compromise fins, or stock fins beat over with a hammer to raise the stall speed(probably can't buy those any more). Get a shifter that lets you easily shift from first to neutral and reverse none of that ratchet action, unless you go with reverse manual valve bodies.