nitrous36

My car has 93k and some odd miles now. Should I continue running GTX or switch to GTX high milage? I change the oil every 3k milesso wouldit really matter or make a diff?

Also I have ablower now. So should I considerusing syntheticor will the dyno oil hold up just fine with the regular 3k mile change intervals. Im just scared that swithcing to a syn this late will hurt the seals and remove to much of the old oil that helps the seals and hurt the motor or clog the pick up in the pan. Will dyno oil be just fine so long as I stick to the regular3k changeroutine?

mustangrich

I'm a self-proclaimed newbie so take my input with a bag of salt.

I worked at a VW and Mercedes dealership for about a year and had switched to using Castrol Syntec in my Mustang at 40k miles about a year or so before. The Mercedes only take Mobil 1 past a certain year and the VW's used Castrol Syntec. I learned from the VW guys that Syntec is not really synthetic oil...something to do with it not really having any actual synthetic base stocks. The Benz guys wouldn't put anything in anything that wasn't Mobil 1. The guys all sang the praises of synthetic oil. I went from Syntec to Mobil 1, though I can't honestly say I noticed any difference. There are a lot of articles that talk about synthetic vs. regular oil.

My girlfriend's '95 Taurus was a complete pile with 127k on it when I decided to put Mobil 1 in it. The thing leaked and wept everywhere and her uncle, who had been a tech through the '70's and '80's, told me I was a flaming idiot for putting synthetic in it. He said it would degrade every seal in that car and I'd wind up doing the change all over again after mopping all the oil out from under the car. The Benz guys said that this was old thinking because cars from back then (exactly what year depends on make and model) all seals and such were made out of an older rubber that would be corroded by the synthetic. Synthetic oil on a modern car, regardless of how many miles you have, will not do any damage that was not already done, however it may remove dried up old chunks of oil that are clogging already marginal seals.

Well, my girlfriend's 3.8L Taurus did not leak and her uncle kept telling me I was lucky. I kept running Mobil 1 in it until it was wrecked. From all I've read and been told, I'll never use anything but synthetic oil again. But, on the other hand, if you do your oil and filter changes with regular oil every 3k miles, I doubt that your engine is in all that rough shape or that you'll have a great deal of sludge to contend with anyway. You shouldn't have a single problem switching to synthetic. You'll spend more, but the cooling and lubrication qualities are (supposedly) superior and you can go 5k miles between changes. Some oils advertise longer intervals and some cars claim to go 10-13k, but no tech I've ever talked to has thought that was a good idea. Some people tell me I'm an idiot wasting money changing Mobil 1 every 5k, but I do it.

raz54

GTX high mileage. The high mileage oils have additives to keep the seals from leaking which regular oils don't have.

nitrous36

But there is one morething to consider. My car has a procharger on it now. Since I have a supercharger do I necessarily have to use synthetic oil? Or would I be fine if I keep using GTX or switch to the highmilage stuff?

v6stang07

personally i would run synthetic because it will offer u more protection than even ur conventional high milieage....it will offer that and some and especially since u have the blower u will want an oil that will be able to withstand the additional abuse

eaglecatcher

Mine has 67k miles on it, and about 2500 miles ago, I went from regular dino, to a synthetic blend, and I could tell my engine was smoother, so this time I'm gonna switch to full synthetic, probably Mobil 1 and then do it myself and make up the difference for the cost of oil. I figured that instead of going straight from dino to synth, I'd do a blend in between. Maybe its a stupid idea, but some people say changing betweend differnet oils all the time isn't great for the car, so I don't know.

either way, I'm gonna go full synthetic soon. I think as long as you've kept your engine maintained, you'll be fine.

raz54

Valvoline make a high mileage synthetic oil. That's what I put in my gf's car.

eaglecatcher

what do you put in your car?

mustangrich

I have always been told synthetic only in turbo charged engines. I'd assume the same would apply to SC'd engines for similar reasons.

eaglecatcher

and that is flipping stupid.