$ for trans rebuild?

[1990LTD]

Mechanic thinks we should try filter/trans oil change before anything else since it's cheaper than a trans. If this doesn't work, I'll order that used trans tomorrow.

[Pirate]

Mechanic thinks we should try filter/trans oil change before anything else since it's cheaper than a trans. If this doesn't work, I'll order that used trans tomorrow.

If it's slipping, an oil change is only going to make it worse, lol.

[1990LTD]

I don't see how flushing the shitty dark fluid (which might be a contributor to my problem) for some new shiny red stuff and replacing the stock filter (as in, 19 years old) will make it worse, but I'm not the expert in this. How's that work?

[1990LTD]

oh yeah, it doesn't do whatever it does when the car is cold. Start it up in the morning and drive...fine. Only when some heat gets into it does it start to "slip"



I've said before that I don't know if it's actually "slipping" since this is the first time I've dealt with it. Either way, it's doing something it's not supposed to. fingers are teh crossed.

[1990LTD]

forgot to mention that he wants to try a bottle of Mucas transmission fix. At this point I'm willing to try anything that doesn't involve pulling the transmission.

[CheeseSteakJim]

I don't see how flushing the shitty dark fluid (which might be a contributor to my problem) for some new shiny red stuff and replacing the stock filter (as in, 19 years old) will make it worse, but I'm not the expert in this. How's that work?

The old fluid has tons of old clutch material floating around in it that's helping the old transmission function. When you flush it and replace it with brand new fluid it takes out all that clutch material that was actually keeping the transmission functioning. If your transmission failed after replacing the transmission fluid, it wouldn't be the first one to do so.

[1990LTD]

That makes sense, thanks. So if it happens like that, it was going to happen eventually anyway, I'm assuming.


Any thoughts on the working when cold but funky when warm?

[Outlaw440]

Heat is the enemy of automatic transmissions. Likely if the trans is on its way out, it only gets worse when its hot. It wouldn't surprise me if it cooked itself on some hot summer day and it's just getting worse and more prevalent now.

[1990LTD]

thanks Outlaw.


just checked the fluid because I'm at work and it's slightly dead so I had a few minutes to start it up and let it run. I must have been in a darker environment when I checked it last because it's not very dark at all...and it smells fine. No debris, though there were what seemed to be a few TINY air bubbles on the dipstick when I brought it back out.


The thing upshifts and downshifts like a motherfucker, just when I'm putting along at like 1k in 3rd does it start to hiccup on me. If I put my foot down a bit further and bring it to 1.5-2k, it accelerates just fine with no hesitation or hiccups. Doesn't happen coasting downhill even though it's still in the same rev range. Basically only happens when I'm putting around town in 3rd with very very light throttle (once I'm in 3rd, that is)

[gadget73]

For some reason when transmissions are on their way out, a fluid change is usually the nail in the coffin. You can try it, but don't get your hopes up.

The getting funky when it warms up is the trans fluid thinning out with heat. It makes less pressure when its thin, and doesn't function as well.

And I still say your problem is not a trans slip, but an engine misfire.

[1990LTD]

zero hour..I'm leaving work in a few minutes, picking up a jug or two of oil (might as well change that shit while he's under there, it's due in 1k anyway), then right to the mechanics place. I'll know in a few hours whether or not my problems were solved (postponed?) or whether or not I need another trans.

[91waggin]

And I still say your problem is not a trans slip, but an engine misfire.

This.
Here's what I think:

A tuneup is cheap. You can do it yourself. It probably needs to be done anyway, and it can't hurt anything even if it was done recently. Three or four times now I have thought the trans was slipping and it was really an engine misfire.

Just like heat is the enemy of transmissions, it is also the enemy of electricity. When wires get hot, they have higher resistance. In your case, the heat of the warm engine might be just enough to start screwing with the spark.

Also, IMHO, any mechanic who's recommending an additive "just to see" whether it'll fix a problem should instantly become suspect. Any mechanic who's worth his salt will be able to tell the difference between transmission slipping and an engine misfire.

If your engine is misfiring and your transmission is fine, introducing some sort of additive may actually cause problems where none existed beforehand.

FWIW, I've never had any kind of good results, and often had bad results, with "fixes-in-a-bottle." I think they do more harm than good.

[Smokestacklightnin]

I agree with the others, this sounds like an electrical/ignition issue. Most trannies on their way out will slip worse the more load you put on them. Plus the history of the vehicle also can help (ex-taxi, trailer towing, or police car due to long idling and heat build up). I recommend using performance plug wires due to their heat resistance and insulation, i have bought new cheap plug wires only to develope misses shortly after.

[1990LTD]

For some reason when transmissions are on their way out, a fluid change is usually the nail in the coffin. You can try it, but don't get your hopes up.

The getting funky when it warms up is the trans fluid thinning out with heat. It makes less pressure when its thin, and doesn't function as well.

And I still say your problem is not a trans slip, but an engine misfire.

I have all new ignition parts on their way to me, they're going in as soon as I get them. A tune-up was going to happen regardless. I hope that's the problem.



also, I have had no reason in the past to doubt the abilities or diagnosis of the mechanic I take my cars to. Lots of years of repairing and maintaining my families cars and all of the cars died of old age, not misdiagnosed or unnoticed problems. That's not to say I think he's infallible, I've just never had a bad experience.


thanks again for the concern, ideas, and discussion, fellas. it has been much appreciated.


worst case scenario: I buy the Mustang trans I found today with fewer clicks on it than mine....and it's not from a parts car, it came out of a Mustang GT in which he upgraded the trans so he doesn't need this one. He's even coming to visit his mom in my town next week so he can deliver it if I need it.

[1990LTD]

I agree with the others, this sounds like an electrical/ignition issue. Most trannies on their way out will slip worse the more load you put on them. Plus the history of the vehicle also can help (ex-taxi, trailer towing, or police car due to long idling and heat build up). I recommend using performance plug wires due to their heat resistance and insulation, i have bought new cheap plug wires only to develope misses shortly after.

wires are actually the only thing I haven't gotten yet. Scott recommends ford racing wires and that's what I'm gonna buy, or at least some other variety of performance wires. any recommendations if i can't find the fords locally?


my car has been a civilian its entire life. i don't know how a fleet car got sold to some old dude without actually being a fleet car first, but it did.