440guy

Hi, I have my first Chevy..I had to come to the "dark side" from Mopar due to our growing family. I just bought a 99 2500 4x4 454 Suburban with 62k miles. One owner. Very nice shape!! It has a miss at idle once in awhile after warmed up. Speed goes up and down. NO check lite is one. Prior owner said he did 500.00 in intake gasket on it. Probably original plugs. I picked up some new ones. Plus I bought a new fule filter. has original intake system. What gives with the idle?

Other than an K and N filter to go in the factory box, DO the after markets have same 2 plug ins that factory intake box has? I see you disconnect those and the thing shuts itself off. Does K and N intake system have the plug in locations?

I think I may have the 410 gears..Big Dana back there. My revs are 2700 or so at 75mph...p265 16 tires...80mph is closer to 3000 rpm...
Seems like it could be locker......I live in MN --I had it in 2wd--and began to spin tires to check...passenger one spins first..then few seconds later--seems the driver rear tire locks and begins to spin...I was checking to make sure it wasnt a ghost spin..like rears can do in dirt and ice...it stayed spinning....Is this correct?

Guys give me some other performance ideas......IE---I do some towing...and looking for mileage.....What chip is best as well?

Go easy on a new Belly button guy!!

73shark

Welcome to the forum.

Recommend AC/Delco plugs and a couple of bottles of Techron.

Don't know if the 99s had the G80 locker diff or not but you can check your option codes on the label in the glove box. Or you can check it here.

440guy

Thank you!
It has the 4:10 sure grip, posi, anti spin, rear end...found out there are onl 3 others like it! Great data base....I on a hunch had already put down a little bottle of stp cleaner from walmart...may have cleaned it up some...will use the techtronic...

Do you recomend K and N filter or entire system? or any kind of a chip? thanks...

Jeff

73shark

Not real big on CAIs (even tho I had the GM one on the '07) or other "performance enhancers" like chips, TB spacers, etc.

If you want to go fast or better mpg, don't buy a three ton SUV.

440guy

Thanks again. Actually gas mileage is no different than my 360 03 Durango. 14 or so. Ya, a 6000 lb brick trying to go through the wind. I am surprised they don't get 5 mpg. I will buy the K and N air filter and call it a day. Will be using it also to trailer my 71 cuda to the drags.