I have a 99 Ranger XLT 4X4 extended cab with an automatic trans. This truck is new to me, I only had it for three weeks.

When the truck is cold the trans shifts thru the gears real nice and firm. After the truck is warm the trans will engage harshly with almost a clunk on the 1-2 up shift and just as bad when it down shifts while coming to a stop. Truck has 163K and the trans fluid is full and doesn't smell burnt.

Any helpful thoughts??

Possibly a bad gasket between the valve body and the tranny case. Two hints on yours that make the gasket suspect 1) the model year and 2) trouble happens when hot but not cold (tranny fluid thicker when cold than when warm).

Do you plan on self help to fix this or will it surely be a shop visit?

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2004 Ranger FX4 Level II, 5R55E, Sonic Blue Pearl

Proudly JAP/RICE free since March 2000

Is the speedometer working properly? Any ABS issue? The VSS can cause these issues along with a shifting issue on the 1999

I would check for codes, even if the light is off.

"Losers focus on winners, winners focus on winning" TB12

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2004 Ext Cab, 4WD, 4.0, Auto, 154k. (4.0 engine is out of a 2009 Ranger w/96k) ( as of 7/1/2017)

2004 Ranger, Ext Cab, 2WD, 3.0, 5 speed , 4WABS, crank windows, no cruise, Edge 116k.(6/5,2014) (SOLD).
1999 Ford Ranger, Reg Cab, 2.5, 5 speed, 2WD, no AC, 150k (SOLD).

I also seem to have harder shifts when transmission is warm. I have the 5 speed auto.

where is this gasket? is it easy to get to the valves?

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98 Mazda B4000 4x4 31" tires
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The valve body gaskets, there are two, are a problem in the late 90s trucks. There is a TSB that Ford issued where the gaskets and separator plate were replaced with a plate with gaskets glued to both sides. I am not sure about the symptoms mentioned in the TSB, but I would imagine it depends on just where the gasket blows out.

Drop your transmission pan and look around the valve body for pieces of gasket sticking out. The area around the round reverse servo is common, as is the area near the solenoids. Check for pieces of gasket in the pan. If you find gasket problems you can have it fixed for reasonable money if you can find an honest transmission man. I would probably go to the dealer and get the TSB done, unless you feel able to do the work.

I had this problem in which I ended up replacing the valve body, problem gone. I never had the od light go off either. So just because the OD light doesnt go off doesnt mean that it isnt a solenoid.

Thanks for the info everyone! I'll check it out.