I've done gone synthetic in tranny & engine (3mpg increase)
 

i;m squealing like a little girl..
more-so because i know i bought a 130K mi car >5 months ago that has never had a transmission oil change.. so i also went synth engine oil.

edit: so far 3mpg FE increase (11.5%).

Q: aren't almost ALL automatic transmission fluids these days synthetic?

A: idk, but i have no doubt that my 1986 car had 1986 tranny oil in it.

I don't have my spec book handy, but there are a few that still use the older formulations.

One note about going synthetic: Not all fluids are compatible with synthetic fluid. Ford had an issue with torque converter shudder and gave it a band-aid fix of using Mercon V (actually a synthetic blend formula, not pure). When done properly it wasn't an issue but if the fluid was mixed it lead to all sorts of problems. The proper way was to drain not only the pan, but the torque converter as well. This step was often overlooked by professional techs as well as backyard mechanics. This lead to seal failure and eventually transmission destruction.

I'd recommend asking in a model/manufacture specific forum about using newer fluids in older cars. It might prevent an expensive lesson.

If it's a high-quality synthetic like Amsoil ATF I'd not hesitate to use it. That ATF will work with many applications. If the transmission specs some form of Dexron or Honda Z-1 ATF the Amsoil will work well.

if it is the 1986 under your nick, keep some oil filters handy. Synthetic likes to remove gums, it is normal.

the more crud the quicker it fillsthem, heavy filters are not a bad sign, it means it is working. Good choice, syntheic, for most brands anyway. :thumbup:

good tips. i'll watch out...
i can wait until 3000 miles,either way, right?

As long as you check your oil frequently for awhile.

Your first synthetic change should be at or near 3k, the rest of them can be longer, if you're comfortable with extended oil changes.

I wish I'd taken a pic, but I ran the same oil/filter in Cara for 10k+ miles and only added 2qts, one to replace the MMO as it burned out, and one at 5k miles. After all that time with 0w30 oil, the engine oil was still clean and honey-colored, not black. I wasn't running an air filter for most of that, either.

I've heard lots of stories about synthetic oils doing harm to engines and transmissions, and after further looking into each claim, I've always found that it came down to user error. Most people think they know things, and don't ever bother to read directions, and that causes problems.

I don't care if I've done something 100 times on 100 vehicles, if I get a new vehicle, or anything changes, I read the directions. There's a good reason for it, and I have a track record of NOT screwing up as a result.

hey, uh, do i have to worry about the tranny filter getting filled/plugged?
my tranny filter is inside the tranny.. unaccessible. lol.