Almost my same story, but I had a Case 1840 and bought a TL26. All I can say its, the best piece of equipment I ever bought, what a workhorse. Let me try to answer your questions. I think I may have an extra parts and service manual (send me a PM)
drop the belly pan and change the oil, I use 15w40 filter Baldwin B109
fuel filter, open the back door and look just forward of the right side of the radiator, yep thats it and it aint easy to get too, make sure you fill it up, before you install a new one
(wix 33386/Napa 3384)
Hyd filter is on the left side, on the side of the hydraulic tank (Baldwin BT398)
Air filter PA1667 Baldwin
My serial number says use motor oil, but Ive always used hydraulic fluid AW68, seems to work for me for the last 2 years
I would change all the filters, so you can start a good maintenance program. The hydraulic and fuel filter can be changed easy by opening the cab. There are two bolts on the cab mounting bracket, on back of the cab and above the engine access cover/lid. Remove the two bolts (I think a 15/16" wrench)now it should take two people, pull/lift forward on the cab, its hard to get started to move, but once it starts it gets easier. Tilt all the way forward and now you can see almost everything. Have bucket on the ground when tilting the cab. I have took another skidsteer and tilted the cab, when I didnt have help, hook a chain on the back of the cab and pull forward.
Pins and bushings, mine are in need of repair, but I just sold the machine today and will deliver on Friday. There is really not a cheap way to do this, Takeuchi will sock it to you, if you get them to do it. If I was going to replace mine, I would probrably take it to my local small machine shop and get him to do it right. You might get by with just replacing the pins for now, it will help some, you can get them from the dealer, they shouldnt be that much and they are harden bolts. If you want to do it yourself, you can get by with a piece of cold roll steel and just drill a stop bolt in the end.
Now to the hard question, turning. need more info
Is the engine at full power, I run mind full throttle, if Im working it hard. if you are running it slow it will do this. If you still have the problem, jack and block the machine and rotate each side of the tracks, listen/feel of the final drive, can you feel or hear anything unusual? check out the track rollers, do you have one that is bad and binding?
If you dont find anything wrong, it could be the track motor, you can exchange the motors, (switch sides) It maybe a PITB, but its a way to troubleshoot the motors.
OK almost finished, my typing finger is getting sore. When I first got the machine, it costs me $350 to learn this solution. The machine started acting up and didnt have any power, took it to the dealer. HUMMMMM How stupid, I felt when I picked it up. The aux hydraulic foot pedal, was not returning to neutral and bogging the engine down. I wasnt using the aux pedal, but I was resting my foot on it and I guess I was pushing on it. It was also real hard to start, when it was in this mode. This problem and a $400 starter, is the only problem Ive had, it now has 3500 hrs on it and uses zero oil. I did change the tracks and sprockets about a year ago, what a PITB, first side took 2 1/2 hrs, other side 45 minutes, its called a learning thingee.
There are used parts for these machines available
Be sure to change all filters, before troubleshooting a problem like yours, to make sure this isnt a issue.
Good Luck, great machine and the 130 that replaced the TL26, is even better, the 150 is like a small dozer, boy that has power
Sorry for the long reply