I have an 01 Dakota 3.9v6 with 134k. I have been thinking about switching to synthetic oil instead of conventional. Ive heard the synthetic is better for the engine and makes them run cleaner but is it a good idea to switch with that many mile on the truck. I drive the truck alot and put a quite a few miles on it in a short amount of time. I have been changing the oil every 2800 to 3000 miles. Whats yalls opinion on it?

 

this time i used Pennzoil full synth. no problems with it. its a little more expensive up front but you only have to change the oil like ever 5k. most stuff now that is not full synth. is a synth blend. your choice really.

 

Well, first of all synthetic will not create leaks, it will find them. With over 100k miles, your seals are wearing out. You may not have any leaks right now, but synthetic can and will find them.

Now, if your leaking bad with synthetic, it may not be economical to switch to it. It's quite expensive, and having it leak all over the place can get pretty pricey.

The benefits to synthetic is yes, it's a "cleaner" oil in that it keeps the engine cleaner. It lasts longer, generally 5-7k miles, some use it for longer intervals. It's got better sheer resistance, and overall is great stuff.

Now, using synthetic is a higher mileage motor, like i said, can and will find leaks. However, if you switch to a dino/syn blend, you can lengthen your change interval, generally to 5k miles, get the benefits of synthetic but with less of a chance of leakage, or at least less leakage.

My best advice would be to switch to a dino/syn blend. But make sure you use a good quality oil. The thing with blends is there is no person or anything that says how much synthetic has to be in the oil to make it a blend. Cheap brands will use less synthetic than better quality brands and also will use less expensive additives.
My recommendation for oil brand is Valvoline. Their synthetic blend is almost a 50/50 blend if I remember correctly. In fact, their high mileage oil is a synthetic blend, and it can help prevent leaks.

Hopes this helps in your decision.

Just wanna let you know, by asking about synthetics, you've opened a can of worms. There are a lot of opinions and a lot of facts, and many many people will chime in. But in the end, do your research on non-biased places and make your decision.

 

my truck has 90k and i switched the synthetic. i can tell the oil is staying cleaner longer then before. by me its only another $2-3 more a case. 4.7L's take 6 quarts.
i use castrol 5w30 (syntec?) i only let it go 4k miles before i change it.
i could get away with more but it's easy to change the oil. and upgrade ur filter, anything but bottom shelf. i use frames extened guard xg16

 

I would go with synthetic. I switched at 112k with no problems what so ever. The first time you run it, change it out at 2500 or so. It can clean a lot of sludge and build up out, so you want to change it sooner the first time. And if you have no leaks, you're good to go. I really don't think you will have any problem. I would switch to synthetic. They are all good choices; Valvoline, M1, Pennzoil...

 

I have 126,000 on my Dakota, I also have a 3.9 and all I use is either Napa or Carquest conventional 10W30 and Napa Proselect or Carquest Red filters. The oil is made by Ashland (Kentucky), who also makes Valvoline. Wix makes the filters to Napa and Carquest's specs.

I have had no problems with oil leaks at all and my truck might burn maybe half to 3/4 of a cup of oil over a 3000 mile oil change interval. From 65,000 to about 85,000 miles I used to run Valvoline Maxlife then switched to Napa brand High Mileage, but my truck was a bit sluggish on HM oil, and I got a little less MPG on it too. HM oil is at the thicker end of the viscosity scale. My truck runs very well on plain 10W30.

I never bought into the synthetic hype, and although Maxlife is a synth blend with seal conditioners, I still changed it out every 3000 miles. I have heard and read at high mileage it is bad to change to synthetics, they will either cause leaks or find leaks due to the increased cleaning properties will wash sludge away from seals and engine mating surfaces and give the oil a place to leak out. I don't know if any of that is true. I have also heard of guys who change to synth at over 100K and have no problems at all. Personally, I would not do it--the risk of problems is too great, if you ask me.

Check out www.bobistheoilguy.com and look in the oil forums, you will find more info than you ever imagined on this very subject.

Jimmy

 

thanks for all the input. i think im gonna switch to the synthetic on my next oil change. What is better a synthetic blend or full synthetic and what brands do yall recommend?

 

well u are probably using a blend already unless u specifically have been putting in conventional. royal purple or penzoil is my choice.

 

Pennzoil, M1, or Valvoline I would say. RP isn't really worth the money. It's so expensive because it has an additive to help you, should your engine run out of oil... and unless you plan on doing that, not really worth it.

 

ive heard of people going 10k with RP, with just changing the oil filter at the oils halflife.