I've got a 99 dakota, 3.9L, 5-speed, 2 wheel drive. It's got just under 200,000 miles. Runs great, but this morning it stared to shake while accelerating. If I let off the gas the shaking goes away. If I accelerate in neautral it doesn't shake. I'm thinking this is a transmission problem. What do you guys think?

 

200,000 on a 5 speed? No issue when in neutral? When was the last time you replaced the clutch? Sounds like you might be due for one.

 

it could be a bad u-joint to.

 

Start here - U-joint = much cheaper than clutch

 

its a U-joint i had a ford that did the same thing

 

I'll third the u-joint motion. 200k is about the most they will go; even if that isn't the issue you should change it if its original.

 

Thank you all very much. looks like I know where I'm starting. I also heard that the 3.9 has an issue with the timing set going out. I was thinking about replacing that while I was at it. any feedback on that?

 

OK, update time. After the initial problem started I went out to the truck and took it for a spin around the block and few times. No shaking...went a few and days and it came back. The problem is not consistant. The shaking is not consistant when it happens, it's not steady. It feels like sputtering like the truck is going to stall, but the RPM will be up over 1500...any further ideas?

 

Check the Idle Air Control valve. It's mounted on the back side of the throttle body. Remove the throttle body and there are 2 torx T20 screws holding it in. See if the pintle end is all caked up with black crusty junk. Clean it off very gently with a shop rag soaked in carb cleaner. Don't drop the IAC or handle it roughly or you will need a new one regardless. Make sure the O-ring is in good shape too. While you are at it this is a good time to clean the throttle body and lube the pivot points for the throttle plates, lube the pivot points for the Throttle Position Sensor and all the linkages on the throttle body too. Reinstall it with a new gasket, they cost about $1.50 at any parts store. A bad IAC may not necessarily set a trouble code from the PCM. It's a good idea to clean the IAC once about every 20,000 miles.

Jimmy

 

As I understand it a surging sensation is sometimes caused by a dirty tps as well. If that's any help.