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One more time,,,,regular vs synthetic!

I have not been on here for a while so this might have just been discussed…sorry !

I have always been the type to change the oil and filter at around 3000 miles. My last vehicle was a 1995 Suzuki sidekick with 173000 miles. I started using synthetic oil (mobil one) a couple of years ago because of the engine mileage, the short trips 3x a week to a dialysis center, (about 1 mile each way), cold starts in winter, and the fact that even in 5th gear the rpm @ even 55-60 mpr, was 3-3500. At 65 it was really screaming.

I just got a 1997 Dodge Caravan wheelchair van w/v6 (3.8?) with only 52000 miles. I plan to keep this for a long time. Has anyone had good or bad luck with synthetic vs regular oil? I know the old story of just changing regular oil @ 3000 miles, etc, but I am still concerned about cold starts and more idling than normal and short trips. Any horror stories using synthetic? Thanks!

opps…sorry…one more question? Knowing the history of transmission problems w/Dodge vans, how about the same question w/synthetic transmission fluid?

The recommended fluid for this transmission is now ATF+4, and it is synthetic.

Synthetic will offer you a little more protection but if you are doing your changes at 3000 mile intervals consistently, you don’t need to spend the extra money. Conventional oil works great, especially at that short interval.

I’m not aware of any horror stories connected with synthetic oil, or at least no valid horror stories. Years ago, some people believed that changing from dino oil to synthetic would result in gasket leaks, but this was disproved.

If you are going to continue to change your oil every 3k miles, dino oil is really not a problem. However, if you live in an area with a very cold winter climate, synthetic oil really will allow you to start the engine more reliably in extremely cold temperatures and it will give better protection at those very low temperatures.

My suggestion, if you switch to synthetic oil, is to stretch your oil change interval to at least 4,500 miles in order to reduce the extra cost of the synthetic oil.

I’ve been changing regular motor oil at 5K mile intervals for many years with no problems, regardless of mileage. Some of the vehicles I did this on were still running well at well over 175K miles.

I still don’t see any reason to use synthetic oil unless the owner’s manual for a vehicle recommends it. The manual for my '97 Acura says I can use synthetic if I choose, but I cannot extend the oil change intervals, which are 7,500 miles. As I said, I use regular oil and change at 5K miles.

It’s your money. If synthetic makes you feel better, by all means go ahead. I’d see if the owner’s manual has anything to say about it first, however. Unless there’s a prohibition it certainly won’t hurt anything.

Since you change the oil at 3,000 intervals you should be OK with regular motor oil. If it takes you more than 6 months to rack up 3,000 miles then synthetic makes more sense since you are leaving it in the car over 6 months.

In the winter the synthetic has a slight advantage over regular especially if it get very, very cold where you live (such as International Falls, MN). You can use regular oil for your summer driving and go with synthetic for the winter without doing any harm to your motor.

I’ve kept 3 vehicles over 250k miles with regular dino oil.

And 2 over 250k miles using synthetic.

The difference was the three vehicles using regular oil started to burn a little (1/3 quart every 3k miles) oil and saw some blue smoke at startup. With synthetic…never burned one drop of oil even after well over 300k miles between the 5k mile oil changes.

There are no horror stories about synthetic. If it makes you feel more comfortable, then I’d recommend using it. Peace of mind is worth a few extra bucks.

Thanx all…I may have mislead a few by saying I change the oil at 3000 miles…that was before I became disabled and my driving dropped to about 3-5000 YEARLY. So I went to synthetic and changed once a year or about 5k miles. Cold starts are common and now I’ve noticed the van gets REAL hot (not the temp gauge)…from under the van as it rolls up by the drivers window, after running the a/c in traffic for a while. I stopped at a drive-up sub shop and was surprised, although it makes perfect sense, how much heat is produced etc. I could see that running the a/c at idle for an extended time could cause a car fire!
And thanx for trans info…I was thinking of going to synthetic there also…now due to heat situation, I think it would be a very good idea. Thanx again all

This is a lipstick on a pig situation. If you want to have the best chance to make high mileage in your vehicle start with a quality vehicle.

In reality your longiviety problems will probably come from systems other than the engine (emission controls,AC,interior trim,suspension with a heavy emphasis on emission controls, AC and transmission) and there is not much you can do for design compromises.

I would not pay top dollar for top of the line lubricants,just the grade and schedule called for,all its going to take is one transmission rebuild or one compressor explosion for the repair to equal the value of the vehicle.

If your vechile is close to combustion due to idling with the AC on you have a problem as this is not normal.Get this checked out.

I lost an engine because of no oil but never because of any difference between synthetic and petroleum base. Neglect trumps any other factor when talking about oil. I have a Chevy 4.8 engine with roller cam so I use synthetic because I saw an impressive Castrol Syntec infomercial. They dropped the car from a ten story building, removed the gas tank, crushed the car and a month later the engine was still running.

Some years ago, I tried Mobil-1 on a car or two, and every time I did, the oil sender started leaking large quantities of oil, and had to be replaced. Oh, sure, probably coincidence, right? Wrong.

On my 2002 Sienna, I have been using Mobil-1 and no problems at all.

I am in extended usage right now as an experiment, not sure how many miles it will be, and hope to lab test the oil out of curiosity. I mentioned this some time ago, and it will be this fall before I get back to the States and have it tested.

Yes, yes, I know it makes sense to just change it, etc., etc., but I want to see what happens.

thanks Oldschool…about the heat situation. “close to combustion” might be pushing it on my part but I am still getting used to the van. My Suzuki Sidekick with a little 4 cylinder didn’t put out much heat! I was just surprised when I stopped at the drive-up window, put the window down and was greeted with a blast of hot air. I think this is “normal” for this type of vehicle. There should be vents on the top of the hood or side of the front fender but they don’t make them that way. (what I need is the Buick vents etc!) I am sure once you get driving down the road the heat is of course blown away. However, I am sure these types of vehicles have fires due to the cat converter overheating due to extended idling etc.
I’ve had big cars before that really crank out the heat but I said…that little Suzuki 4 cyl. didn’t put out much heat! Thanx again!

No there is not any type of vehicle that catches fire due to any part getting hot because of idling.Think cop car.

I have sat for hour on I-10 here in AZ while it was closed due to accident with the truck idling and the AC on and cars for as far as I could see were doing it also,no fires.

The only reason I respond is that other people read what you post about cars catching fire because of idling and if no one challenges it some truth is imparted on your statement,nothing personal.