I have a 2000 mustang V6 automatic and there is no service engine light on or anything but it goes through the gears fine and when it gets up to 4th and 5th gear it revs up from 4th to 5th when the car warms up it doesn't do it whenever you just first start and go down the road just seems like when it gets warm and up to temp does anybody know what this could be is it slipping and forth to 5th gear I've checked the transmission fluid and the transmission fluid is fine and red I'm just wondering if it's the IAC doing it or something else hope you guys can help

 

Hello,

I moved you into Sn95 Section You were in 2015 Up Section.

Being as it goes away as it warms up Shooting from the Hip I would try some Fluid Conditioner in the trans. Could be Morning Sickness where the Seals are Hard and as it Warms up they Soften a bit. A Fluid & Filter Change would be Nice as well! Anyhoo thats the Quick Answer. Do you Know History of Vehicle as Far as Servicing? How Many miles on the Car? That is Just My 2 Cent's !

Something Like this! But Don't Overfill Trans!

https://www.summitracing.com/parts/l...+5ba26a96cdb6b

KC

 

It actually starts when it warms up and not at start the guy had notes of stuff he did to it like oil changes and stuff I'll have to look and see if he did a transmission pan gasket filter change as well but it just seems weird that you know it runs so good no service engine light or anything it's just when it goes to 4th to 5th after it warms up it doesn't want to shift to fifth from 4th and what do you think about the Lucas trans slip stuff is it a yay or a nay was looking up and it also could see like this solenoid inside of the trans yeah hopefully it's an easy fix because first through 4th is good

 

Oh it is an automatic and sorry for the word jumbo talk to text LOL

 

Okay thanks

 

160. 000m

 

Checking the Service Records is a Great Start! I've used the Conditioner over the Years and sometimes it Helps!

FYI,

KC

 

I got to thinking. A 2000 Mustang is a Four Speed Automatic. I checked the Owners Manual as well and it says Four Speed 4r70w. So anyway must be 3 to 4th Issue??? Does not Change my Advice Just made me Wonder!

KC

 

I think I'm still going to change the solenoids anyway possibly just to go ahead and clean the transmission and give it a oil change and you know just the reconditioning it anyway and I'll add some of the conditioner as well after I change everything does that sound good

 

As you know it couldn't hurt LOL Although it is an old model that's always good to keep up with the records as well so after I go ahead and do that I can write it down and then keep putting it in the book👍 and thanks for all your guys's help trust I will be putting more back on here it's an old car

 

Into Every Life a Little DRAIN must Fall! Glad to see un FILTERED enthusiasm for your Car! There is Two Puns for Ya!

Good Wrenching!

KC