Bogging Down Sound in Overdrive Question

[Fred Garvin]

I recently got this 2002 Sport (4 L; SOHC). When cruising down the road in overdrive, and I go up a hill, the engine accelerates to try to maintain speed. While doing so, it kinda groans and there's a slight vibration in the steering wheel. Once it's back to cruise speed, it's not noticeable anymore.

I can recreate the groan if I hit the accelerator in OD--it increases speed, but the groan becomes noticeable. If I accelerate it so that it kicks out of OD, the groan is no longer there. Nor the groan there if I hit the OD/off button so that it not's in OD.

It's almost a bogging down sound like when a spark plug wire is bad, but it only appears when in OD under an increased load.

Am I frettin' over nothing? Any ideas?

 

[Eneurb]

Sounds like it may be torque convertor shudder. How is the fluid?? When was it last changed??

 

[Fred Garvin]

I just got this Explorer, so I doubt the trans fluid has been changed. I did check the trans dip stick and the level was slightly below the cross-hatched area (running, hot, in park). I have not put anymore in because I'm thinking of changing it anyway.

Do you think the shudder (that's a good word for it) is because of low or bad fluid?

 

[mctoy]

Could be old fluid. When you replace the fluid, put in a bottle of lube gard (About $10) Most mfr's use this as well as most trannie rebuild shops. About the only 'additive' that I or most guys wholeheartedly recommend. Might consider synthetic fluid as well if your changing it. Members here have reported good MPG gains and quieter tranny with it. I'll be doing the same to mine in a couple thousand miles. (Dealer just did tranny warranty work and put in new MerconV) Mobil1, Amsoil seem to be the preferred fluids here. Good luck!