I bought a sm 420 tonight for my cruiser for $150 bucks with clutch and flywheel!!! I now am planning on buying the adapter for a toy mini truck and bolting up my dual cases. Sound like a good idea?
I will be adding a v6 toy mini rear axle and running 4.11 gears with lockers. Should give me a good low crawl ratio.

Must be the going rate. I just picked up my 420 last week for $150. I also got the bellhousing, clutch fork and shifter.

Jason M has the same setup in his Cruiser.

OTT made the adapter for SM420 to Mini case.

Sounds like a reasonable idea to me :)


http://imagem.webphotos.iwon.com/1000031835/1000031835_29200393358PM0.6565958


You will have to move the rear axle back a bit tho..
and create a new tunnel cover.

This is on a 40 right?

yeah its all new, two years ago. thats a bad thing about this board, mostly someone has done it and posted pics. :flipoff2:

Well, new to me at least. I just need the adapter from the SM420 to the toy mini box. Who has the best adapter? AA or OTT or ???

AA supports the board;)

I just checked their site and didn't see a adapter for SM420 to toy truck t-case. I saw that marlin makes one as well as OTT- I'll have to call tomorrow....
Jason M- are you running a 23 spline imput or 21 spline? I have 21 spline and am wondering if it is tough enough behind a 350.

Originally posted by 85toyboy
Well, new to me at least. I just need the adapter from the SM420 to the toy mini box. Who has the best adapter? AA or OTT or ???

AA does not make a sm/mini adapter

Your choices are Marlin and OTT

Mine was the first adapter that OTT made. It is not on the website yet.

Differences between the marlin and the OTT adapter.

OTT makes a new mainshaft for the SM420. Marlin adapts the mini case for 10 sp input.
Personaly I like the fact that I do not have to replace a special gear if the Tcase input breaks. Not that I have heard of it happening but...

Also the OTT unit is clockable. Short of a 4" by 6" 1" lump in my skidplate I have a flat 31"x38" long bellypan..

Marlin's will probably be cheaper.


21sp input and 23 sp dual case.

Camo is running dual 21 spline tcases with the Vortec V6 and nitrous. And it has held up.

You can always upgrade at a later time.

Thanks for the info. How hard was it to change the main shaft in the tranny or do I have to take it to a shop/
How long did it take to get the OTT adapter? (I heard they were slow)
Do they have a phone number- I emailed one of them and have not heard back.

Special gear or special shaft, what are your chances of breaking either? Especially since it's before most of the torque reduction ocurrs. The input gear seems like a lot less work. The clocking sounds like the best benefit.

I was just watchin the 2000 Warn rock crawling champioships with my boy (I was supposed to be reading him a book ;) ) There was a cruiser competing with a sbc 350, auto, dual case, and V6 mini-truck rear end. He hammered that thing and it looks like the only thing that broke was the cruiser front end.

It was the rig ALL-PRO builit and was in a mag a few years back.

I think it is a good economical set-up if your tire size does not get big time.

....better pull that book out....

Originally posted by 85toyboy
Thanks for the info. How hard was it to change the main shaft in the tranny or do I have to take it to a shop/
How long did it take to get the OTT adapter? (I heard they were slow)
Do they have a phone number- I emailed one of them and have not heard back.

It was simple to change the main shaft. Did it on my workbench with no press. Only a hammer and a bearing puller.

I got the first unit.
so they did a lot of testing before they sent it to me.
Delay should not be that bad. But really it is for them to say how long it will take.

I'll PM you Ricks #