The Stovebolt Site Forums The Shop Area Engine Shop need help

just got back with my 52 halfton truck via towing service, left the house to get gas and was at a red light at interstate,a little bit of a incline,another car was about 1 foot from my rear bumper, truck did not go into first, shifted again,released the clutch,something sort of popped,vehicle would not go into any gear, it is a 4speed, truck is lowered so I was not in a good place to even try to work on it so I had it towed to the house,I hope that it is just a linkage problem and not the transmission,my question right now is this stock drive shaft any different to undo then the other modern type,any thing in particular that I should look for when I do get under my baby....Thanks for any help...Fred

when the engine is off will it go into gear? If so it sounds like the linkage broke somewhere. If you're still wanting to take the shift lever out you push down on the retaining ring at the top of the housing and turn counter clockwise if I remember corectly.

Good luck!

assuming this is a top loader, you might have popped the shifter out of it's proper place.. It happened on an old GMC with a NP 420..but I was stuck in first gear. I ended up yanking, beating, spanking and screaming for about 2 hours before ole boy walks over, smacks the retainer off and pulls the shifter handle out of the cover.. we reset the handle and it was off to the races.. You also might have sprung the pressure plate or wore it out, hence the "pop".. does the clutch pedal feel any different?

T. Mott and Dr.Fatfenders. thanks for your quick reply, I just had my wife to shift the gear selector and I could only see movement where the lever is attached to the transmission,I could not see any other movement from the other selector levers, I have not jacked up the truck yet, I was trying to see linkage movement from under the hood side, will jack it up tomorrow and see what it looks like,I have a cheap 2 ton jack but maybe I can get it high to work on it,thanks for your help. will advise later,,,, Fred

If you still have a stock floor in the truck you can get to everything from the top if you take the floor panel out around the transmission, it's big enough to pull the transmission completely out through. If you have the SM420 granny box you won't be able to see anything move from the outside, all the linkage is contained within the transmission. You can pull the whole top cover off or the side cover and check out the shift forks and stuff, it's pretty easy. Put the tranny in neutral before you try to re-assemble it. Felpro has new gaskets.

4 on the floor,thanks so much , I had forgotten about the floor, I do have the stock floor, not sure if I have the sm240 trannie, I know that it is a later then 55 model sagnaiw.I was dreading getting under the truck tomorrow, I may still have to but at least I can go into it without doing so first, my body at my age does not like to get under a truck unless I have to. Thanks again,,,,,,Fred

Joker you can reach me at [email protected] abut that tranny

Joker
do not rely on a cheap 2 ton floor jack, please use solid axle stands befor you sqeeze your aging body under the truck. Now you know why we poorists keep our truck high and unchanged. :-)
SAFETY FIRST TRUCK SECOND

Good luck, keep us posted

You said you could see movement of the shift levers and you said it was a 55 or later Saginaw, so it's not a SM420 top loader. Is the shift lever stripped on the shaft that goes in the trans? You might try shifting the levers by hand. Are they stuck? The shifting fork might jave dent or slipped out of position. You'll probably have to disconnect the levers, drain the oil and remove the side cover to look around in there.

have bent

His tranny is an SM420.It does have the original torque-tube .
I am guessing that his u-joint assembly has broken.I had the same problem with my 52 GMC 1/2 ton where the yoke which slips on the driveshaft end cracked and peeled the tube part of the yoke off the yoke itself
It was a little difficult getting the twisted metal off the end of the driveshaft but once it was off, the replacement worked fine on the shaft end.

Zach, I can't get your e-mail to work either, states that your mail box is not available, my e-mail is [email protected]

Mech/Luke, you and others are correct about the u joint as being a source that might be broken,it is broken on the rear yoke with about 1 inch being left on the propeller shaft, and about 1 half of it is all that is left on the spline, guess I will just replace the whole u joint from Jim Carter's,he gets $110 for the complete assembly,unless someone knows where I can get one cheaper. Thanks to everyone for their tips and concern. I almost drove Luke crazy with my e-mails,I may not be thru yet.......Fred

No question asked is a bad one. Fred, I am glad to help anytime I can.
I wil look and see if I can locate a used one but there are different ones.I will need a pic or measurements.

Boy, you just busted my bubble, I thought that they would be standard, being that Jim carter has one listed under part#me1233 that is called for on a 4 speed,I think from 50 to 54?later,,,Fred

I stand to be corrected, it should be from 48 to 54......Fred

Yes, somewhere in 54/55 they changed to the open driveline

I should be getting my u joint assembly tomorrow but I am a little concerned about the propeller shaft sleeve ball/bell.should I have to replace it, what is the process, it is a little scorned on one edge, I took some emory paper and smoothed it out some, dont know if it has always been this way since I've had it or if the broken piece of the yoke got some metal on it. Thanks,....Fred