55 HD5 transmission question

Weather is beginning to clear so I've been running my grandfather's 5 a bit more. For years my dad has always said take it easy on her and run in just 1st forward and reverse. The other day I thought I'd just see what she felt like in 2nd reverse. No go...now, I didn't play the clutch etc...but it will not easily go into any gear other than 1st in both directions. The shifter is real loose so I'm not sure what I can do to tighten up the detent but if there is an easy solution I'd appreciate it. The dozer runs great, leaks from the final drives but all in all the people around my house job cannot believe the dozer runs and pushes so well. If anyone knows of something fairly simple to do to check it out please advise. Any yes all fluids are brand new. I don't think my dad dropped the fluid in the transmission since 1965 but all is new now. Also, while I'm thinking about it where can I get gaskets for the Lubefiner oil filter. When I changed the oil filter I reclamped in the same area but now she leaks a bit. TY

for a quick check you could pull the shifter out and manually shift the forks with a long screwdriver or prybar and put it in one gear at a time and see if the dozer moves. you can then fix the shifter. common wear item. i use 2nd reverse alot even though it wears the tracks faster. i push alot with 2nd forward until i get too much on the blade then down into first. works good for me. look in or get a parts book to see how it comes apart. good luck

Time to find a friend with a welder, lathe and mill. That can be refitted with a little time and effort.

Thanks for all the replies. Not sure why my email didn't alert me as I chose that option...?
I'll have to get in there and take it apart and see for myself. Thanks much for the pictures! Yes, this machine does have the high speed reverse but I never remember my dad using it as he would always say this is not a "production machine". He never ran it hard as he knew it would wear things and the machine was not making any money to replace things that went bad due to "pushing" the old girl too hard. I know on the job we pushed the newer machines full throttle and every pass was money...I remember once getting yelled at because I started a bad cut with a big cat scraper and backed her up...boy was that a mistake! I think I was 14 but I never did that again.

great find in bringing a old post back 

It's kind of trial and error method , the cross shaft that bolts index into can be any length as the side bolts are what holds it in place ( it allows forward and back motion arc )  the bolts need the ends turned down to fit into drilled hole in cross shaft , so again they need to be long enough and full threaded bolts ( length into shaft will be set later ) the pin that goes into cross pin will be sizes to take up wear in that yoke and will be larger that stock one , length of that pin will go through yoke and extend a small amount - to hold that pin in position is where the flat on each side needs to be ground so the 2 side bolts can hold it into cross cross shaft  ( tension on pin can be controlled by shimming bolts ) so they just meet pin sides but not so tight it prevents movement . 

This is whatni gotz....the pin went bye bye! I'm guessing it lives down in the bottom somewhere ?

Also only drain is the differential. If you have milky oil use diesel or n it and run for a short time and refrain several times. Don’t run too long the needle bearings between input and output shaft won’t like it. There will always be sludge in the bottom. Check gasket on top of differential as they leak water in a lot. I also changed the boot on the slide lock to a seal as the boots I bought did not last.

Thanks guys for the advise... ill start getting something together shortly.