SD22/23 transmission swap

[acce]

Hi guys,

 

I own a 1982 720 SD22 diesel with a 4-speed gearbox and I'm thinking of upgrading to a 5-speed. I found a 5-speed manual transmission from the SD23 engine, will this fit my truck or do I have to look for a gearbox that's originally from a SD22?

 

Thanks.

[datzenmike]

Welcome to Ratsun.

 

SD25 5 speed front case.

 

 

We only got the SD22 and SD25 here and both only with a five speed. Check they are the same length, they should be. Starter should be on the left side as viewed from inside the vehicle. In any case your four speed front case could be swapped onto the five speed but if they are both SD engines it should fit just fine.

We have one or two Finland members here.

[wayno]

Does your 4 speed transmission have a plate with 6 bolts holding it on just in front of the shifter like in the photos below?

 

[datzenmike]

He'll be getting up in a few hours wayno.

[wayno]

Just trying to make sure his 4 speed is like ours, you never know what was shipped to other countries.

He'll be getting up in a few hours wayno.

[acce]

Thanks for the answers guys.

 

Does your 4 speed transmission have a plate with 6 bolts holding it on just in front of the shifter like in the photos below?

 

Hi wayno, I haven't been able to disassemble my current transmission yet, since the car is in winter storage right now. Will start working on it again in a few months from now.

[wayno]

I suspect that the SD23 transmission will bolt right to your SD22, I mean why would they make a middle diesel engine(between the SD22 and SD25 with a different pattern.

Thanks for the answers guys.

 

Hi wayno, I haven't been able to disassemble my current transmission yet, since the car is in winter storage right now. Will start working on it again in a few months from now.

[datzenmike]

Don't need to disassemble it. Just look forward of the shifter. If 4 speed it will have a 6 bolt cover plate with a small flat round breater cap on it...

 

[acce]

Ok, thank you very much. Will be getting back to this when I start working on the truck again in spring.

[wayno]

The reason we are asking about what 4 speed you have is because if it is the type in the photos above, you can take the front case off of your 4 speed, and put it on a 5 speed of the same type out of another Datsun/Nissan from the late 70s threw the mid 80s, then you would not need that SD23 transmission.

Ok, thank you very much. Will be getting back to this when I start working on the truck again in spring.

[acce]

The reason we are asking about what 4 speed you have is because if it is the type in the photos above, you can take the front case off of your 4 speed, and put it on a 5 speed of the same type out of another Datsun/Nissan from the late 70s threw the mid 80s, then you would not need that SD23 transmission.

Ok, thanks. That gives me a few more options. 

 

Found a transmission from a 4x4 720 with the same SD22 engine. Would this fit or are they different?

[wayno]

The 4X4 transmissions did not have the speedometer drive hole in them, unless someone put a 2wd transmission in it in the past, so if it doesn't have the hole in the tailshaft housing, you will not have a speedometer.

Maybe you could have the hole machined out, I don't know, but that would require you pulling the rear housing off, maybe you can do it using the 4 speed case speedo hole for reference on the size the hole needs to be.

I believe that all the transmissions have the speedo drive gear on the shaft inside, but I don't know that for sure.

The 4 and 5 speed rear cases/housings are different, and are not interchangable, also the 4X4 transmission you found, what year is it, early transmissions are the long ones(31 inches), while the later 4X4 transmissions are the short ones(26 inches), you likely have a 31 inch 4 speed, so you will need the long 5 speed.

Ok, thanks. That gives me a few more options. 

 

Found a transmission from a 4x4 720 with the same SD22 engine. Would this fit or are they different?