Diagnostic/video 5 months ago VIDEO: TCM Service Share Tweet Print Email Underhood Service Staff Writers, View bio Bio Recent Posts Popular Posts Register Now For The Women In Auto Care Summer Leadership ConferenceNGK Hosts YANG Regional Meet-UpEco-Absorb Simplifies Repair Shop Spill Clean-UpFederated Auto Parts Recognizes Top Supplier PartnersDENSO Teams Up With Safe Driving Experts To Help Reduce Auto Crashes In Communities Throughout North America Ford Diesel CK-4 And FA-4 StatementGMC Tech Tip: EVAP Vent Solenoid Replacement (P0449)Sunex Tools' Socket & Bit Set Features Mini RatchetLocate Leaks With Redline Detection's Dual Purpose Diagnostic Leak LocatorRotary Lift Expands Remote-Controlled Mobile Column Lift Lineup Andrew Markel debunks the myth that the TCM learns how the customer drives the vehicle. steve woody also note that the radiator cap plays a role in the transmission fluid. A bad cap will push fluid out the coolant system when the engine is hot. The coolant system on todays cars is very critical to cooling the engine and transmission fluids. When having a bad cap on the radiator, it pushes the coolant out the system. Sometimes causing blown head gaskets, cracked heads, boiling transmission fluid and making it gritty. When that happens the spools in the trans. valve get stuck and makes it hard to shift. Driving it to long like that, will burn up a transmission…… years of experience…. I’ve seen this so much. That I preach about the cap to all my customers.. Steve Woody/ Owner of Mobile Master Mechanic in South Carolina. GOD BLESS AND MERRY CHRISTMAS.