The Stovebolt Site Forums The Shop Area Driveline 4 Speed Transmission question

Members:
I have a 49 4 speed tranny,( iN A 54 3100) How do I check the fluid level? I pulled the carpet,and tranny cover plate...I can't find the dip stick....nothing in the engine compartment...
I just got the truck and I want to flush all fluids ( Kerosene or diesel ). I JUST CAN'T FIND WHERE TO POUR IT.
PLEASE HELP A NOVICE.

There is a pipe plug about 1/2-way down the case (I think on the DS then there is a drain plug on the very bottom rear. Take the plug out on the side and feel around for oil in the case if you cannot feel it add (through the same hole)until it just starts to come out the hole. If it has not been changed in decades you may want to drain it followed by a kerosene wash (refill with Kerosene and run it back and forth in the driveway a few times). It takes something like 2-1/2 quarts I think to fill it (should be in the owners manual). Good luck.

THANKS..

ok...I just cleaned the top of the tranny...got this number
GM4 591688......On side B 149, # 4 GM 591665...So what do I have ? and where is the fluid check and filler?

confused.

silly me...top # is 591568...bad eyes...

Should be the SM420 4 speed with granny low used from about '48 to '67.
A shop manual would be helpful to you.

Thanks for the Info...I wanted to get alittle more specific than the general years...Also,I have the shop manual and Owners manual, I can'f find instructions on checking fluid level or changing/filling...but then again I'm cleaning with kerosene and alittle loopy.
Thanks
Again.

Drain plug on the bottom, and filler plug on the passenger side (about half way up the case). Fluid/lubricant goes into the u-joint housing from the transmission (if you still have the enclosed driveshaft).

Tim:
I saw the drain plug...and noticed the passenger side plug...
Now the passenger side is the fill side? I guess I need a flexible filler tube.... I have an enclosed driveshaft, Do I fill the U-Joint somewhere ? or does it get fluid when I put it in the right side hole?
Also, I removed my speedo drive,cleaned it made sure it spun..is there a washer/gasket between it and the tranny housing,or is it metal to metal ( mine didn't have a gasket).
And...can you decipher the tranny numbers to get a specific year,so I know when asked. It is a 4 speed with a granny and a side port for PTO..
Thanks for helping

I will not attempt to identify the year of an SM420 transmission. Here is general information:
http://www.novak-adapt.com/knowledge/sm420.htm

Date code info here (after you narrow down the years from info in the link above):
http://members.cox.net/cglabe1/SM420/sm420.html

As stated above: "Fluid/lubricant goes into the u-joint housing from the transmission (if you still have the enclosed driveshaft)." That is also described in the Owner's Manual and/or Shop Manual.

Filling through that hole can be done with one of the plastic fill bottles with the tapered neck. Usually gear oil comes in those containers. I use 85W90 in mine.

I bought a pump that attaches to a gallon jug for transmission and rear end filling from the local parts store. They're only about 10 bucks and well worth it.

I have used the techniques described by truckernix & Avette4me.

This last time, I was lazy and took out the shifter rod and filled the transmission from the shifter-rod hole in the top.

Well, I learned that you can suck the oil into one of those bottles if the occasion demands.

By the way, buried somewhere in the shop manual it talks about the fill level as being at the bottom of the hole when warm or 1/2" below when not warm. You may want to observe that.

Again, Thanks for all the good info.
How about the gasket between the speedo drive and the tranny housing? Is there one or metal to metal contact...
Thanks

I think there is no gasket in that location.