transmission oil change

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Empire402

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Any Dex3 fluid will work; Dex6 full synthetic is backwards compatible but not necessary. If your filter is the cloth variety (probably is, if you're having delayed engagements cold only) then toss it in the trash and install a screen style filter. Never use the cloth type - they suck. Use a regular composite style pan gasket (no cork or rubber - they both leak) and no RTV on the pan, gasket, or mating surface.
Just wondering if you had any recommended brands/part numbers for the fluid, screen style filter, and composite style pan gasket? I need to service the TH350 in my 81 K10 soon and just want to get the right parts and would appreciate your input.
 

Ricko1966

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time to change the transmission oil and filter, any suggestions??
I have a suggestion. Put a drain plug in the pan.Drain and fill the transmission pan at oil changes. Yes it will only by a 4 qt swap but 4 times a year,and your transmission will always have relatively fresh fluid
 

NickTransmissions

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Just wondering if you had any recommended brands/part numbers for the fluid, screen style filter, and composite style pan gasket? I need to service the TH350 in my 81 K10 soon and just want to get the right parts and would appreciate your input.
Ditto what @Ricko1966 said; check Mr Gasket for a rubberized gasket with steel inserts, think they make one for the TH350. If you cant find it, composite gaskets are fine but DO NOT use cork or regular rubber as they both leak. Fluid is your choice. Trans fluid is heavily regulated so any DexMerc certified fluid will be fine. Same for the screen style filter.
 

AuroraGirl

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Ditto what @Ricko1966 said; check Mr Gasket for a rubberized gasket with steel inserts, think they make one for the TH350. If you cant find it, composite gaskets are fine but DO NOT use cork or regular rubber as they both leak. Fluid is your choice. Trans fluid is heavily regulated so any DexMerc certified fluid will be fine. Same for the screen style filter.
my favorite is the fluid claiming to meet or exceed the specs for Mercon/Dexron III and Mercon V and Dexron VI AND Mercon LV and Dexron ULV
 

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