m211 with 302gas to cat 3208

[General007]

This is all new to me just got a gmc m211 from my uncle and was wondering if the 302 is a good motor or should I swap it to a cat 3208 seeing I have one lying around. I dont want to change the tranny or anything it has the automatic. This is all very new to me so any input would be nice.

 

[hippiedude]

The 302 is a good engine .... Lite on power , but still a good engine ...... I don`t know if a cat motor will bolt up to a hydromatic and it probably don`t fit in the space that you got to work with ....Check the truck out the way it is you may like it ... I do .... Tim ....... PS and they are easy to work on .............

 

[m109guy]

If it ain't broke, don't fix it.

If the current engine runs fine, then leave it be. As hippiedude stated, I doubt you will be able to fit the cat into the engine bay and be able to mate it to the hydromatic transmission.

But if you are feeling adventurous, then by all means. If you do, please make sure to document the work for the rest of us

 

[General007]

Thanks guys I guess I'll have to see how it is then and if it is fine I'll just leave it until something goes wrong with it. The other thing is not that its a huge deal what should I be looking for average fuel mileage with this thing not that I'm going to drive it on long trips but is 5 to 10 mpg in the ballpark or is it worse or better. And being a new guy to all this is there anything I should be checking or looking for to begin with in this truck.

 

[Rockcrusher]

hello everyone when swapping a diesel into where a gas engine was your rpms have a great influence diesel won't rev as much

 

[Stan Leschert]

Like M109guy said,
If it aint broke, don't fix it!

The 302 is a good engine. The weak point was the tranny.
When it ran fine, evertything was good. The inability to select your gear was a major PITA!. Years of experience, tought you how to get around the system, and operate the beast correctly. If you must put the CAT in, match it with a suitable tranny.

 

[General007]

Is there anything that can be done to the tranny to make it work better??? Is there things I should check into on it before running it???

 

[Stan Leschert]

The tranny adjustment procedures are in the TM.
Make sure that you only use 30 WT NON-detergent oil in it.
Detergents will rot your seals.
Other fluids may be superior, but unless you want a mobile oil slick.....

 

[General007]

thanks for the info on these things hopefully all is well with this truck im getting, I'll post some pics when i get the chance and where do i get these manuals for a m-211

 

[Stan Leschert]

PM sent! Let me know if I can help.

 

[Stan Leschert]

Here is another site that you can try.
MilitaryTrucks.ca Website - M135

 

[rosco]

Is there anything that can be done to the tranny to make it work better??? Is there things I should check into on it before running it???

Service the whole truck - check everything, even down to the air in the tires. Tune it up!

I have had several 211's and drove them numerous times, all over the North, from Prudhoe Bay to Southern Alberta. One was my daily driver. That was back when the AlCan was still fun to drive. It was paved with mud then. One thing I always remember about the M211, is flying mud. Sometimes it would get to raining and the road would get sloppy. The front fenders are pretty flat and straight forward - the front tires throw mud straight ahead and some gets up in the air. You then run into it & it gets all over the windshield, until you have to stop & scrape it off.

Its a great deal of work to change the transmission to a 5 speed. I did it once - you have to change the T-case too. Its a single speed. Then the Front axle doesn't engage right, unless you shift that to forward/reverse, manually. You also have to hang a clutch pedal in there too.

Anyway, the 302 is a tough engine. By todays standards, its not a lot of power for that truck, so don't get in a hurry, or think you are. The gas milage is 8 or 10 mpg. The tranny is not that bad. You have to learn to drive it though. Get it in the hills, and you will use the "Hilly" side of the box. That holds it into each of the 4 gears, and allows it to only shift at max RPM's You will watch the speedometer and learn the shift points.

They moved a lot of stuff for me - equipment, wood, livestock, even several cabins.

Lee in Alaska







Keep it timed correctly. If it gets retarded, it will break exhaust manifolds to crack.

 

[General007]

Alright thanks for all the info guys from the looks of the thing I've got a good deal of work in front of me to restore it back to original. Im hoping to keep most of it stock but do some slight mods to it to enhance the power and look of the rig. What tires would someone recommend for it cause it looks like they will need to be changed and I really like the looks of the "bobbed" deuces but is that a pain in the rear to do. What I ultimately want is a unique look with some slightly bigger tires but everyone will know that its still an old army truck. Thanks again guys for the help