[L_zap]

I have a 2000 V6 5-speed and I want to change out the oil in the transmission. I'm hoping my shifts can become cleaner/smoother after changing it. I have a few questions...
I've read that people say the manual transmissions don't need to have their oil changed? My Haynes repair manual says to change the manual transmission lubricant (same as saying the "transmission oil", right?) every 60K or 2 years. So, which should I follow?
Also, the manual says to use Mercon ATF (5.6 pts for T5 and 6.6 for a T45). How do I know which I have?
I went to AutoZone and was told that it requires synthetic ATF Mercon V, the manual says Mercon, not Mercon V. "Mercon V is not interchangeable with the regular Mercon fluid"
Ive read through some of the old threads and am getting mixed answers. Some say they're interchangable, some say transmission oil change isn't needed...any replies would be appreciated. Thanks.

[93mustang]

I talked to Tremec about fluids for my T-5z.
Dexron III is what they reccomend. I have the Valvoline brand in mine.http://www.valvoline.com/pages/produ...asp?product=64
You can also use GM synchromesh, or Penzoil brand synchromesh for more severe duty.
The only synthetic that they reccomend is Mobil, which is the only synthetic that they actually have tested.
Follow this link for more information.
http://www.allfordmustangs.com/forum...ng-5-0-lx.html

[90 stock stang]

Manual trans fluid change is needed, just not as often. Auto trannys tend to dirty there fluid quicker and can damage more parts. If you pull the fill plug on your tranny and the fluid comes out clean on your finger then it is probably ok.

[L_zap]

The car has about 108K on it, so I thought it would be useful to change the oil. Is Mercon and Mercon V interchangeable? The manual says no, some say yes..
I bought this oil http://www.mobiloil.com/USA-English/...hetic_ATF.aspx and it says it's good to use in Mercon and Mercon V required vehicles. Should I go with it?

[90 stock stang]

I would say to stick with what the manual says. I know there are better products out there but if you keep the fluid clean then everything should be ok after all the original fluid was in there for 108,000 miles with no problems.