Sm 420 Swap

[69 FJ40]

Hello all,
New to Mud and the cruiser world. I just bought my first FJ40. It is a 69' stock in working order. It has the f engine, 3 speed, 2 speed transfer case shifter in the dash and a factory PTO. I am thinking about the sm 420 swap. What should I know and keep in mind. How challenging is the swap and what do I need and need to do to complete it. Any help, advise and suggestions would be appreciated. Just want to know what I am getting myself in to. Thank in advance.

 

[lcruzrlvr]

http://www.ih8mud.com/cruisertech.php

Scroll down to Transmissions.

Your biggest issue will be the adaptation of the shifter for the transfercase.

 

[esh]

Mudrak (www.mudrak.com) is close by in Sonoma if you need to talk with someone. Lots of great resources online and in your area. G'luck!

 

[69 FJ40]

Thanks guys I will look at the tech links and also consult Gary at Mudrack. Do I need to lengthen or shorten the drive shafts?

 

[FJBen]

are you wanting crawl ratio? or why are you doing this? I ask because if it's a daily driver, the Sm420 is not the friendliest of tranny's. Frankly it's a bit on the annoying side compared to the sweet shifting toyota 4/5 speeds.

If I had to do my setup over (which i might) I'd opt for an H41 or an auto/orion setup if I were going to daily drive and wheel. Don't get me wrong the 7:1 first is awesome, but the tranny is very clunky and pretty slow shifting.

 

[Cruiserdrew]

Thanks guys I will look at the tech links and also consult Gary at Mudrack. Do I need to lengthen or shorten the drive shafts?

On the drive shafts, both will need to change-the front will get longer and the rear will get shorter. Do not have this done until your swap is complete. Then you measure the flange to flange distance and take that measurment to your drive shaft shop. They will set them at the proper length.

The SM420 makes a great swap.

 

[pjohnson]

There is also Ron at Custom Cruisers FJ40 in Gilroy 408-842-3540.

May be slightly closer than Sonoma.

I don't know what your timeframe is, but I will have a low-mile rebuilt SM420 available this winter when I swap it out for a H41/Toybox combo.

Phil

 

[69 FJ40]

This is not my daily driver, but I do plan on driving it to and from my trail runs. The H41 is a Toyota 4 speed?

 

[69 FJ40]

I am definitely closer to Gilroy. I am looking at my options right now phil, but please do pm me when your sm420 is available. I might be interested. Can some one give me an cost estimate on this swap Thanks again.

 

[rusty_tlc]

This is not my daily driver, but I do plan on driving it to and from my trail runs. The H41 is a Toyota 4 speed?

Yes it is, the non-us H41 is desirable because of the low first gear.

I lifted this from Marlins site the formatting didn't come across very well but the information is there.

Land Cruiser Transmissions
Type Speeds Years First Gear
J30 3 speed 59 - 9/73 2.75
H41 4 speed 9/73 - 9/90 3.55
H41 Non-US 4 speed 9/73 - 9/90 4.93
H42 4 speed 9/80 - 9/87 3.55

 

[Pin_Head]

If you use the Advanced Adaptors adaptor, you can keep the PTO drive. If you use a plate adaptor, you will lose the toyota PTO drive, but you may be able to use the Spicer PTO drive on the sm420 case. With the AA adaptor, you will be lengthening the front and shortning the rear drive shafts.

 

[woooody]

Hello all,
New to Mud and the cruiser world. I just bought my first FJ40. It is a 69' stock in working order. It has the f engine, 3 speed, 2 speed transfer case shifter in the dash and a factory PTO. I am thinking about the sm 420 swap. What should I know and keep in mind. How challenging is the swap and what do I need and need to do to complete it. Any help, advise and suggestions would be appreciated. Just want to know what I am getting myself in to. Thank in advance.

I just picked up an sm420 with pto in Sacramento. But I don't think you can use that PTO.

Honestly, if it were me, I'd either go with the non-us H41, or the SM465.

As far as cost, sm420 may be cheapest, depending on how you source your parts. Seems more and more guys are opting away from the sm420, so you might be able to pick up a used set up for a reasonable price.

Gary did all of my work. You can't go wrong using his services, just plan on waiting to get in to see him.

 

[bustanutley]

Your biggest issue will be the ad... to do is lengthen the rod 3" and hook it up.

 

[69 FJ40]

Humm...thank you guys for all your input. Now I have to decide. It looks like the non-us H41 is more popular choice. How hard is it to find these? Anyone can give me costs on either? Thanks again.

 

[Poser]

Humm...thank you guys for all your input. Now I have to decide. It looks like the non-us H41 is more popular choice. How hard is it to find these? Anyone can give me costs on either? Thanks again.

Not hard at all, you will just need to break out the checkbook...


800.00us is pretty common....



Hit MAF, SOR, and other Land Cruiser parts vendors and see.

 

[Poser]

Then you will also need to find a four speed flywheel housing, since the three speed and four speed are not the same....and then modify your drive shafts, shifter holes, parking brake cable, speedometer cable, etc....



No big deal really.

 

[69 FJ40]

Maybe I'll just keep my 3 speed until it craps out on me. Seems like these swaps are complicated and costly.

 

[woooody]

Doing an sm420 is "cheap" -- Especially if you were to pick up an 420 from someone doing a swap. But if you drive on road much as a DD, you will either loathe the 420, or drive like a grandma.

 

[bustanutley]

I did my sm420 swap for under $600, thats with a new clutch, so if that is expensive?....

 

[Tigerstripe40]

Maybe I'll just keep my 3 speed until it craps out on me. Seems like these swaps are complicated and costly.

I pulled my H42 4 speed out and put in the SM420.

It was super easy, no driveshaft mods were necessary!

I spend $600 on the total conversion, including adapter and new old stock transmission.

I got a new old stock surplus SM420 and it shifts no worse than the stock 3 speeds I have driven. The gear spread between third and 4th is a little narrow, so there are times when third is too much, but fourth isn't enough (pretty rare though).

I daily drive my FJ40, and I drive it to the trail head, and I have no issues with the way it shifts or drive.
The SM420 has to be one of the best mod's I have done to my Land Cruiser.