Is my truck okay!! Help!!

I have a 1999 Z71 Ext.Cab and it has 113,000 on it. I bought it used at 109,000 and after 3000 miles I put 5W30 Mobil 1 fully synthetic in it. It totaly made a difference it how it ran and I got better gas milage too. I have noticed though that people are saying you shoudln't awitch to Synthetic on a vehicle with that many miles...is this true? If it is, what damage have I done?

no damage Mulaka just a waist of money. at 113,000 miles the major engine ware is already occured. Save the extra 3 bucks a quart you would spend on synth oil and save up for inevitable engine rebuild you may have to do. All good name brand oils all have to meet federal standerds, swithcing from one brand to another or from one weight to another is not(I repeat is not ) going to make a difference to your machinery. infact all of the petrolium fuels and oils in this country all come from the same tap they just slap individual company labels on them. Trust me I'm a truck driver I know these things. Exxon may claim to have a special detergent or quality gas but it all comes from the same fuel terminal as the convenience store accross the street. Relax about oil man, lifes to short...JJ

Well, if you just got 113,000 miles, and the truck has been serviced regularly, then you shouldn't have to worry about any overhauls anytime soon.

About the synthetic oil, you probably will develop a leak if any seals or gaskets are wore, and this is only becuase synthetic oil is always going to be thinner and have less friction then conventional oil. I know that's why I wouldn't suggest anyone switching from conventional to synthetic, becuase synthetic will leak faster then conventional oil.

But if you have seen better fuel mileage, and you think its making a difference, then by all means keep on using it (just keep an extra eye out for any leaks).

what year is your chevy truck chevytrucks92? if not a 99 or newer i would respectfully tell you that you sorely mystaken about these engines. There is know way these gen III engines or 99 and newer will ever last like previous years. I say this with sadness becuase i own one. The days of 2-300,000 miles on a GM engine before rebuild have gone...JJ

Hi jumpinjack66, my truck is a 1992 model, 350 (5.7L) TBI. It has 123,xxx miles as of now, and is in as good as shape (both mechanical and appearance) as it was when it was brand new.

It averages around 19 mpg, is a 4 wheel drive, regular cab, short wheel base, automatic, with 3.42 gears.

i'm freakin jelous!!!!!!!!!!!!

chevytrucks92, Would you like to trade? I have a 2000 silv short bed standerd cab 4x4 5 speed 4.8 with all z71 options plus extras i have installed on my own. I am sure value wise i would have to kick in some cash for your truck...lol....JJ

oh ya my milage is 58,000 .... just about worn out...lol...JJ

LOLOL. That is funny! Is it that bad>?

Don't get me started!!!

lol.
http://files.automotiveforums.com/gallery/watermark.php?file=/500/159122rear_quarter_stylineconcepts_2_.jpg

There is a picture of my truck.
People in my family have had and still have 99-up Silveardos, and they haven't had any trouble, lol. But none of them have over 25,000 miles yet. My Papaw has an 04, had an 00 with 36k, traded to the 04, and my uncle has an 03 with around 20k, he pulls that race car in my sig in a 24x8 ft enclosed trailer, and it does fine. But none have many miles yet.

Ya, thats sweet man (nice ride!)

Thanks. I sure can't complain about it, lol. I drive it to school (I go to Morehead State University), and its about a 260-270 mile round trip for me, and I travel it every week. I usually average 350+ miles a week on it, and just last week, it got 19.3 mpg, week before it got 18.9, and week before that it got 19.4 mpg. Only thing I've done to it is Flowmaster cat-back exhaust and Poweraid Throttle Body Spacer. That and regular servicing (I use Valvoline MaxLife and a 16 oz. bottle of STP Oil Treatment in the blue bottle and Valvoline MaxLife Fuel System Treatment or STP Fuel Injection cleaner every 2800-3000 miles). I also run 93 octane gas. But its been a good one. It doesn't use oil nor does it ever smoke.

no damage Mulaka just a waist of money. at 113,000 miles the major engine ware is already occured. Save the extra 3 bucks a quart you would spend on synth oil and save up for inevitable engine rebuild you may have to do. All good name brand oils all have to meet federal standerds, swithcing from one brand to another or from one weight to another is not(I repeat is not ) going to make a difference to your machinery. infact all of the petrolium fuels and oils in this country all come from the same tap they just slap individual company labels on them. Trust me I'm a truck driver I know these things. Exxon may claim to have a special detergent or quality gas but it all comes from the same fuel terminal as the convenience store accross the street. Relax about oil man, lifes to short...JJ

You are absolutley right! I worked at ARCO refinery and we traded with TEXACO. And Exxon had a truck terminal across the way, they bought Ultramar refinery fuel and had a tank called exxon additive that was mixed in as they loaded there tankers. Looked like maple surup to me, (probally is) and they added about a cup for every 3000 gallons.Now they can call it Exxon fuel.