have truck 2 yrs....never did trans fluid...97 4.6 auto...runs fine just worried changing fluid can actually ruin trans...i dont have a clue when it was changed last. its a dark reddish color...doesnt smell,but reddish. what do u think....change just pan fluid and filter?

 

i have a 2000 4.6 and had my transmission fluid changed about 3 month ago and i dont have any problems.
it was the first fluid change and it was really dark red.
i would change just fluid and filter the seal on the pan is reusable

 

Having the fluid exchanged is a good service to have done. It is one of the biggest urban legends ever, internet car forums suggesting that fluid flushes ruin transmissions. That is as absurd as suggesting oil changes are bad, radiator flushes are bad or brake fluid flushes will cause your brakes to fail. It simply is not true. People flush a transmission they have already broken in a last ditch effort to save something already gone, then mistakenly blame the flush. Many manufaturers require transmission flushes now to maintain warranty coverage. Flush it, just use the correct fluid.

Or you can do it like others suggest, change 1/4 of the fluid and the filter. Would the same people just change a quart of oil and the filter on the engine? I wouldn't.

 

I would flush it. I have never had a single tranny slip on any of my cars and I put 150k on a corrolla, 212k on a volvo and I have 112k on a pathfinder. Jury is still out on my Expedition, but I had the tranny flushed and filtered this weekend with 30k. I have always used Amsoil ATF in my cars, but I broke down and used Castrol Mercon V in the Ford since my research indicated that the fluid is engineered a little differently than most ATF fluid.

You don't want all those shavings banging around in there. And believe me, there is a ton of gunk on the magnet after the first few changes. Typically I watch the drain interval but I do use the eye and smell tests. When the fluid starts looking brown-ish or smells burnt, get it out of there.

 

You should change your trans fluid. Just like Big Greenie said, a trans flush can not damage the transmission in any way at all. I don't know how people came up with that one but its 100% wrong. When you do the change the fluid put in a new trans filter and pan gasket on to. Since you have the 4.6 you probably have the 4r75w transmission which takes mercon v. Just to be safe I would check the owners manual and also look at the bottom of the trans dipstick, it should say what fluid to use. As far as the fluid itself any good name brand fluid should do, although I prefer synthetic fluids over conventional but that's just my opinion. Since you don't know what fluid is in the trans I highly recommend having the transmission flushed to get out the old fluid out and new stuff in. If you really want to do it yourself you can buy extra fluid and change it,drive it around for a while and then change it again, to get most of the old fluid out, in my opinion it is just smarter to get the trans flushed.