is it bad gaz

[sp3499]

2000 rodeo v6 60 000 miles 4x4.

this week end i went to my parents house to get my atv with my trailer.on the way back on the high way the tranny was always on overdrive and third gear always shifting back and forth.i put in super unleaded before i left.when i was half way i stopped to put gas in after that the tranny was doing ok allways staying in od downshifting only when going up a hill.i don t think that putting in super had any thing to do with it. m y only guess is that i got bad gaz.after i stopped i didn t put in super. more info my trailer and atv weight about around 1800 lb

[trooperbc]

head wind? elevation gain?

isuzu's aren't particularly fond of hioctane gasoline, actually. and perhaps it had ethanol in it?

//bc

[sp3499]

no gain in elevation i drove the st lawrence river valley all the way and the wind didn t change.it was a 4 hour trip

[Ramblin Fever]

Originally Posted by trooperbc

isuzu's aren't particularly fond of hioctane gasoline, actually.

//bc

Better come have word with my Isuzu then; she's obviously not playing by the rules

My truck in fact THRIVES on 89-91 octane's, HATES 85 octane and will run like crap. Been this way since I drove her off the lot 10yrs ago - dealer tried everything then, new plugs, new computer programing, flashing the computer, etc....she pings horribly on anything less then 87.

What's even funnier, I can take this truck to the flat-lands of the desert, even with 91 octane she will ping, but anything above 6k feet, she's quiet as a mouse, with 87 or above octane.

To the OP: my truck does in fact shift differently if someone has accidently put in 85 octane versus my norm of 89....can't say for sure if that's your issue though, but could be bad gas too.

[Gizmo42]

Either cheap gas (I only use major brands like shell or conoco. Never P66 froze a fuel line with their gas once) or it was an ethonol blend. Ethanol doesnt have the BTUs that gas does and your mileage and power will drop with it.

Mine never pinged till I pulled a 6x12 u-haul trailer with it a few weeks ago. Even with the trailer empty it pinged horribly. I always use 85 octane gas (lowest here). I put in 1/3 tank of 91 octane and it was fine after that.