what do you do to keep your truck in such good running condition with such high miles and with racing it too???? i just broke 109K on my truck and the tranny shifts funny every now and then and the horrible, horrible start up and constant valve train noise is driving me insane. it runs rough and idles funny and one day it will use gas like i have a hole in the tank then the next day its like im getting ricer gas mileage. i have kept very tight schedule on all maintenance. i have tried numerous types of oils and filters to get rid of the valetrain and startup noise. i have tried many fuel additives to try to achieve better gas mileage. so far on the truck i have had to replace the oil pan gasket, lifter cover gasket, and water pump. now the front cover and valve covers are leaking. this is my daily driver with which i will use to tow my mustang to the track this summer. i am still a college student so i cant afford an overhaul on the tranny or the engine and especially with such low miles for a I6. i am so fed up with all the problems that if they arent all fixed by the end of summer im going to sell the damn thing becasue i will need reliable transportation for the 700 round trip miles i will be takin to and from school twice a month.

(phew i vented and still dont feel better)

any and all comments and suggestions welcome

 

Are you sure you have an I-6?

Seriously, though: 3.73 seems like a REALLY high ratio for a 4.9L, unless you have some tall tires. If so; did you recalibrate the speedometer?

 

i have lightning 17's with a 275/60R17 tire

 

Do those tires have the same revs-per-mile as your originals? You can find that spec for most tires at the Tire Rack. If they're different, you need to read this thread.

 

i havnt recalibrated but i am 1 mph off. i dont think my tires or gears have anything to do with the way its running.

 

I really don't do anything special. I change the oil every 3k miles and other than that just drive the hell out of it. You mentioned trying several different oils. I don't have any data to back this up, but it seems like engines that are subject to several different oil types don't last as long as the ones that have one kind of oil over their lifetime. Different oils have different characteristics for viscosity and lubricaton, even if it is only a very small difference. If you break in an engine with an oil and then change to an oil with different properties the engine may not respond well. I know that the engines in my radio controlled cars are very particular about the type of fuel you run in them. The oil is mixed with the fuel, and if you break one in on brand x fuel and then switch to brand y the engine usually doesn't perform as well. Of course these engines rev to 40k rpm which might make a difference.

Most of the sensors have been replaced on my truck, either because they went bad or because I wasn't comfortable with them anymore. Sensors could be causing your intermittent mileage and driveability problems. Don't get the impression that I havn't had to change lots of parts on my truck; the list of repairs is a mile long.

My truck has 3.08 gears, and has done a lot of highway driving. From the time I got my license until I got out of college (8 years) I lived out in the middle of nowhere. I made the trip to somewhere and back (~30 miles roundtrip) 2-3 times a day at fairly constant speed.

No secrets. Maybe I'm just lucky? I do get nervous everytime I run it through the gears even though I doubt anything will happen. Knock on wood.

 

i have changed most of everything. im about to go back almost stock with alot of things to see if i get better responses. i wasnt the original owner of my truck i bought it at 60K 3 years ago and i got a best of 22mpg and it ran good and i dogged it out. ever since i started to take extremely good care of it it has been slowly letting me down.

 

mine runs hard and doesnt burn any oil but i get poor gas milage, even if i baby it...seems like my sensor in the gas tank is off...but im like SS, just change the oil, keep the fluids topped and drive the hell outta it and she runs like a scalded dog all day...