THIS IS A CATERPILLAR D7G TRANSMISSION POWER TRAIN TROUBLESHOOTING TESTING ADJUSTING, LIKE NEW CONDITION!! ,THIS HAS SPECS.AND ALOT MORE,I BUY BOOKS ALSO!!! PLEASE GET IN CONTACT IF ANY PROBLEMS AFTER PURCHASE,BEFORE FEEDBACK, I'VE HAD NEUTRAL FEED BACK LEFT AND WAS TOLD BECAUSE THEY WERE CONFUSED WHEN LEAVING FEEDBACK,THANKS