Hey I have a 1997 xlt 4x4 4.0L automatic trans. When I put it in drive or reverse the rpms will drop and the truck starts to lurch, but when I'm in neutral or park it idles fine, help would be awesome!

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1997 single cab xlt 4.0L 4x4 3" body lift

I will be interested in the posts you get. I just bought a 2000 4x4 auto and it does the same thing. It's like the torque converter is engaging when it shouldn't?

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2000 3.0 4x4 XLT 150,000 miles Stohrm in Portland

Yeah that's exactly what it's like, I'm taking it into the shop on Friday so I can let you know what the problem is

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1997 single cab xlt 4.0L 4x4 3" body lift

So I think I may have found my issue. If you turn off heat/ac on/off to off the truck quits surging. Maybe the clutch assy on the AC is doing something weird. I will be interested to see what you find. THX

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2000 3.0 4x4 XLT 150,000 miles Stohrm in Portland

Just wondering if anyone resolved this issue. I have a "new to me" 99 B2500. It shows exactly the same symptoms.
lw

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lw
99 B2500 with automatic

thats what happens when you shift an auto trans into gear.....the RPMs drop and you can feel the truck move a little if your foot isnt pushing the brake hard enough

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2021 F150 5.0 Screw

Past:18 F150 2.7, 16 F150 5.0, 14 F150 5.0, 07 F150 5.4, 03 Ranger 4.0

Master Certified Ford Parts / Warranty Admin

Understood, my problem is either the air control valve or the clutch on my AC is going out per my mechanic. I don't want to spend the $$$ now, so I just turn off the heater when I'm at idle. Why does the AC clutch engage when I have my heater on?

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2000 3.0 4x4 XLT 150,000 miles Stohrm in Portland

From what I understand, some vehicles are designed to turn the AC on with the heater, which can cause your RPM's to jump and then go down. My Ranger XLT 4x4 (2000) AT does this too.