Hi, i have a 1999 expedition and i was wondering if there would be a problem changing my transmission fluid. It has 211,000 miles and the fluid has never been changed. The truck appears to miss or something at about 30 to 50 mph with no rpm change and under a load, when going uphill.

 

no it wouldnt hurt it. the miss u have maybe time for a tune up.

 

Thanks for the reply.
I have heard that after so many miles that it might mess the tranny up.
As far as the miss, I have order some cop's and the plugs were replaced last year. I held the brakes and revved the engine to about the rpm that the miss occurs, and it ran fine. It seems to only happen around 35 to 40 mph and in high gear and 1300 to 1500 rpm.

 

That's an engine miss. Changing the trans fluid would be a good thing to do, but it won't fix your engine miss.

 

Thanks, Took her by aamco this morning and it was # 1 missfire....3905 times!
They ssaid that changing the fluid at 205,000 miles could cause the seals to breakdown or something like that. I may look into getting a used one from a low mileage vehicle to replace it. Advance used a code reader but it did not pick up the missfire.

 

That's because they want to sell you a rebuild. It isn't true.

 

The best thing to do is to have the fluid exchanged, not a flush, there is a difference in the two. Especially if it smells burnt or is a dark red or brown..that IS a lot of miles.

 

Your 99 has a torque converter drain plug, no need to use a machine. Drop the pan, replace the filter, clean the crap out of the pan, reuse the factory gasket, and drain the torque converter.

You need a new COP on #1.

 

Forgot about that handy drain your TC has.....wish the newer ones had it !!

 

Thanks guy's. It is the #1 coil/plug. I will be changing the cop's this weekend.
A little cautious on changing the tran. fluid. The guy at aamco did'nt trty to sell me anything, he just stated that they have changed the fluid on a high mileage vehicle and within a short time it quit pulling. I don't have a ton of money to shed on a new tranny right now. But if you guy's are right then it should'nt be an issue. just going by stories i've heard over the years.

 

With 211k and the original fluid, it's only a matter of time before the tranny will need a rebuild whether you change the fluid or not.

 

Just changed #1 cop and spark plug. plugs were changed last year from Ford.
Sticker said gap should be .052 - .056
Gapped new plug, Checkd gap on existing plug and it was almost .070
guess I'll have to redo all of them. crap!