2000 Jeep Laredo Whole Vehicle Rumbling

To be able to help you better, we need some more information. After you start it is the exhaust loud? Are any of your engine lights on or anything? Does it more when cold or hot? Can you describe the rumbling better for us? You said it is rumbling but is it accompanied by a certain sounds too? Is your vehicle acting any different when it rumbles, such as loss of power, shifting ok, etc?

I do not notice any exhaust sounds. I do not notice any difference in performance either. The rumbling motion doesn't seem to come with any noise, I think any of the extra sounds are just from things in the jeep being affected by the motion. It shifts normally. I really don't notice any different performance except for the shaking.

The "perform service" light is on, but it is also overdue for an oil change which I'm doing tomorrow.

Since I posted the first time, I've found some possible explanations online- somewhere I read that around 150,000 miles (mines about 142000), the "brakes" ( no more specific unfortunately) cause shaking and jumping, which describes the rumble well. I started my car without pressing the brake at all, and the rumble wasn't there but that could be coincidence as it comes and goes. I then remembered that it also rumbles like that at stoplights sometimes. Just a possibility.

If your perform service light is on, then it could be an issue with you plug wires, spark plugs, etc. This could cause a minor miss and effect the performance of your vehicle over time and you may not notice the loss of power as much over time. Also, under certain cercumstances, rocks could lodge in the bushing for the transmission/transfercase mount which also on some models has the exhaust connected to it. Take a visual of this bushing to see if any rocks are lodged in this bushing or around the area because if this is the case. It could cause your rumbling by transferring the vibration through out the rest of the vehicle. The best thing to do before anything is to get your vehicle scanned at a local auto parts store to see if there is any codes and go from there. A way to see if you plug wires are gone is to have the vehicle running at night and look for arcing where the plug wires are and maybe take a spray bottle and squirt water on them to see if they arc that way. If there is any arcing, replace the wires and plugs too if it has been a while. Your brakes should not shake your vehicle while at a stop unless something is wrong with you ABS.