I have purchased a Cat D7G s/n 92V77xx, it has a multi-shank ripper s/n 28K151. I am trying to find parts to reseal the lift cylinders. The 28K s/n prefix does not show up in Cat SiS parts program. My local Cat dealer can not find anything on it either. The tag is a Cat tag. It says "CHILE: M.R. MEXICO-MARCA RESISTRADA". So it appears it was made in Mexico. My question is where can I find a parts breakdown for these ripper lift cylinders? 
Thanks in advance.

Blake 

There is a cylinder listed under 92V for 3J6429 cylinder GP that is for a ripper set. Is that anything like yours? SIS says it's for a later serial number machine.

Phil,
Thank you for the reply. I put that part number and s/n prefix in SiS but it says No search results available! I cant look at it.
I will look in the library here. I have found a cylinder group 2C6553 that looks close. However it shows a bolt in the head. My cylinder head screws on to the barrel.

I can't find a 2J6429. Was your number supposed to be a 2J6439 maybe? That cylinder has a different style head.

I couldn't make s/n 28K work but the early 92V used a 12G-up #7 ripper (arrangement 9J567 replaced by 3G2022).
Uses cylinders #3J6439
More digging....28Kxxxx is a military s/n equivalent  to the 12G1-up.

serial number 28k no7 ripper 1967 military ,

Magnet and Bruce,
Thanks for that info. The 3J6439 cylinders are not like what is on this ripper. These cylinders have a round head that screws on to the barrel.
I'm going to measure the ID of the barrel later and see if I can determine the stroke.
What I'm needing are the pistons and seal kits. The two pistons that came out are aluminum and do not match. I don't know if the originals were aluminum. But I highly doubt it.

Blake

Bruce,
Would you happen to have or know where I can get a parts break down of what cylinders were used on the 28K ripper.
Trying to see if they used different cylinders that the 12G s/n rippers.

Thanks
Blake

Both cylinder options (correct) are 6" bore x 19.70" stroke (3J-6429 or 4T9290) and have four bolt heads.
I don't have the parts book but you might look into later rippers with s/n 12G7500-up or 82G1000-up to see if they used a different style cylinders.

www.liberatedmanuals.com/tm-5-2410-237-23p.pdf