Is it bad to change my car's gas from unleaded to supreme?

cost to replace both re4ar axles

We wish to have more storage in the back, as we never have passengers. We use it as a dingy behin our motor home.

My truck sat untouched for about a month and the battery went dead. I charged it and started my truck and had to pump the gas to keep it going, it ran very rough. Then after a while it ran fine. Starts good, runs good and drives good, but I have no working gauges and the odometer reading says "no bus or no bu5". I've checked all fuses and connections, not including the cluster in the dash, and still none of the gauges work. Any advice would be appreciated. Thanks

I passed my emissions test back in April 2011 and check engine light is on? And I noticed that the car hesitated when I accelerated from a stop light. OEM HVAC compressor was recently replaced 10/6/2011.

When braking, I get a vibration and noticeable knocking sound from the front passenger wheel area. Would like to have some idea whether this is an issue with the brakes vs. suspension prior to visiting mechanic. Both the vibration and sound have been getting progressively worse over time. Neither are present during acceleration or cruising.

and in drive need help

I have over 226k miles, car runs great - but want to ensure I am using the right oil.

I left the door open and my battery went dead. I tried to charge it, but i can't get it to work. the door don't close the window is a little high above the line of the top convertible what do i need to do. my gas left was 17 or so miles thanks

No check engine lights or computer code indicates a problem, yet when the truck is brought out on the highway the RPM gauge oscillates quickly and the Xterra SE loses power, will stall out, and then will be difficult to start up again until you wait a few minutes. My usual mechanic had the truck for 2 weeks but could not recreate the problem in his garage and would not take it out on the highway because he did not want to get stuck. I picked up the truck last night and it broke down again on the highway with the same symptoms. I had it dropped at the Nissan Service center last night as my mechanic could not figure out the problem. Any ideas?

Replaced distributor, crank sensor, tune-up, fuel pump and filter IAC valve, car ran fine. Started dying at corners now will not start (flashed no bus) across the dash. Not throwing any codes. Can you help me?

driving it. The dealership says if no lights come on they can't tell what is wrong with it. But that have checked everything and the car is fine. The car is not fine and this should be a known issue since people have been complaining about this for several years according to the Internet. How can I get my one yr old car fixed so I can get to work everyday

While driving, service traction control will come on along with the engine light, and they flicker on and off, and cause the car to jerk, the locks to relock, , and sometimes cause the car to turn off.
then i tried to restart engine again it works bu 300 to 500 meters then again jerk and turned off.
i found dirty battery connections then i cleaned it well last night but i am not sure if that the cause of problem

its kinda like it locks up but if you put back in park it will start right back up

Three warning indicator dash lights came on when I had to put on the brakes (from about 70 mph to 45 mph)while I was on the highway.

THen as I began to accelerate all power on the dash would go out for a split second and then go back to normal. The same thing would happen when I put on the brakes.

I am not sure what indicator warning lights came on now. I went back out to check which ones, and the car dash is back to normal. Any ideas?

Also, last week I cleaned the terminals on the battery and now the car has trouble starting and sometimes needs to be jumped. Could this have something to do with the problem I mentioned above?

Thanks! Any help is greatly appreciated!!