So I today I decided to check the fluids in all the cars and I noticed the Intrepid needs oil (no surprise from what I've been reading). Anyway, I went out and bought some oil for it, but now I'm wondering what's in there: synthetic or natural oil? How can I tell the difference? It's possible the last owner switched it to synthetic oil to avoid sludge buildup the 2.7L is so notorious for. I'm pretty sure bad things would happen if I pured regular oil in and it had synthetic inside already. Help would be appreciated! (especially so I can get it done tonight).

Also, when it comes time to change the oil, and after the engine has been steam cleaned (because oil was found on the engine, but no leak was found, and I have never seen a leak), I was thinking of switching to synthetic...to avoid that horrible sludge problem the 2.7L is so notorious for. Is it a good idea?

Edited February 1, 200719 yr by Dodgefan

Synthetic oil does tend to help mitigate the sludging issue along with evaporating less, providing better viscosity at all temps, and being more chemically stable.

Synthetic oil does tend to help mitigate the sludging issue along with evaporating less, providing better viscosity at all temps, and being more chemically stable.

So is it a better choice overall then?

In my opinion, yes. I've had nothing but good experiences with Mobil 1 full synthetic. I use Extended Performance since my car's high-mileage. My father's Bonneville has always had Mobil 1 synthetic in the pan aside from whatever was factory fill. Almost 120k on the clock and absolutely zero engine problems.

In my opinion, yes. I've had nothing but good experiences with Mobil 1 full synthetic. I use Extended Performance since my car's high-mileage. My father's Bonneville has always had Mobil 1 synthetic in the pan aside from whatever was factory fill. Almost 120k on the clock and absolutely zero engine problems.

Well, once the engine has been cleaned and determined if the oil was the result of a leak or just a spill, then I'll probably go for mobil 1. Will mechanics change it to synthetic or is it a do-it-yourself sorta thing?

It's probably for the best, since the 2.7L is so notorious for sludge buildup.

So does it look any different than regular oil when you check it?

I only use Mobil 1. After it's been in the engine a while, you really can't tell the difference. You won't harm the engine by switching. You can ask for synthetic when you get your oil changed. It'll cost more. The cheapest synth oil change I've found is at Walmart. As much as I hate Walmart, they'll do a synthetic oil change for you for less than it costs to buy the oil and filter off the shelf.

As long as you're not leaking oil too bad, you can just about double the time between oil changes. I don't know what your Dodge has, but both my Avalanche and CTS have engine oil life monitors. I judge my oil change time off those and generally get about 12k between changes.

In my 2000 intrepid I run nothing but synthetic and i recommend you do the same because of the sludge problems. A few extra dollars will help the engine in the long run.

Edited February 2, 200719 yr by Buickfosure

I only use Mobil 1. After it's been in the engine a while, you really can't tell the difference. You won't harm the engine by switching. You can ask for synthetic when you get your oil changed. It'll cost more. The cheapest synth oil change I've found is at Walmart. As much as I hate Walmart, they'll do a synthetic oil change for you for less than it costs to buy the oil and filter off the shelf.

As long as you're not leaking oil too bad, you can just about double the time between oil changes. I don't know what your Dodge has, but both my Avalanche and CTS have engine oil life monitors. I judge my oil change time off those and generally get about 12k between changes.

Nah, it doesn't...not even an oil pressure gauge...but then not much does these days. The Shadow actually has an aftermarket one, which I have always liked having. But anyway, I just don't want to go adding oil to the engine if it has synthetic. Hmm...I bought the car at 174k and it says it's due for an oil change at 177k...so I guess it must be natural oil...

Nah, it doesn't...not even an oil pressure gauge...but then not much does these days. The Shadow actually has an aftermarket one, which I have always liked having. But anyway, I just don't want to go adding oil to the engine if it has synthetic. Hmm...I bought the car at 174k and it says it's due for an oil change at 177k...so I guess it must be natural oil...

Could be, but not always. Even when the dealer does my oil change, they put that stupid sticker up on my windshield saying to come back in 3000 miles. It gets taken down before I even turn the key.

Could be, but not always. Even when the dealer does my oil change, they put that stupid sticker up on my windshield saying to come back in 3000 miles. It gets taken down before I even turn the key.

SO how should I go about finding out? Can I call the dealer with the VIN number and ask them what oil they used? Maybe asked what it was serviced for too in the past...?

Oh..does synthetic smell any different? I could use that as an indicator if they smell different...

Edited February 2, 200719 yr by Dodgefan

I know more about oil know than I ever wanted to...

If you're leasing it (which you're not)-I'd use regular oil.

If you buy though, I would use Synthetic...

For the beater (wagon), I use regular oil (quaker State), which it has been running for over 140k now...don't plan on switching its oil....

The wife's car runs runs on Mobil 1, which it has since the break in period.. (10K)...has 30k on it now.

Her cars still runs like new, it takes quite good care of the engine. Even though it runs on mobil 1, I still change the oil

and filter at 3-3.5k. It's not the oil that I worry about, it's the filter, which should be changed around this time.

Though I might upgrade to a K&N fliter...

My other car will also get Mobil as soon as it hits it's break in period (around 10k)

I would go into detail about the types of Synthetics, but it gets quite boring...

Long story short, do it!

I know more about oil know than I ever wanted to...

If you're leasing it (which you're not)-I'd use regular oil.

If you buy though, I would use Synthetic...

For the beater (wagon), I use regular oil (quaker State), which it has been running for over 140k now...don't plan on switching its oil....

The wife's car runs runs on Mobil 1, which it has since the break in period.. (10K)...has 30k on it now.

Her cars still runs like new, it takes quite good care of the engine. Even though it runs on mobil 1, I still change the oil

and filter at 3-3.5k. It's not the oil that I worry about, it's the filter, which should be changed around this time.

Though I might upgrade to a K&N fliter...

My other car will also get Mobil as soon as it hits it's break in period (around 10k)

I would go into detail about the types of Synthetics, but it gets quite boring...

Long story short, do it!

Sounds like I will. So since you know a lot about oil, how do I tell what is in there now?

In my opinion, yes. I've had nothing but good experiences with Mobil 1 full synthetic. I use Extended Performance since my car's high-mileage. My father's Bonneville has always had Mobil 1 synthetic in the pan aside from whatever was factory fill. Almost 120k on the clock and absolutely zero engine problems.

But I bet it still runs like new...

Dodgefan- I've never ever heard of anyone flushing their crankcase when switching to snythetics. How could they NOT be compatable? Is Jiffy Lube flushing oil galleries for your $20 oil change?

Do a standard oil/filter change and put in synthetic (if that's what you want to do) and don't worry about what's in there now.

daves87rs is right: tho synthetics may up your change intervals, many oil filter brands have downgraded construction quality and you would be well advised to change more frequently that recommended/prompted. A good rule of thumb in my book is 50% of recommended (ie: recommended- 12K, change at 6K).

if you have mad cash run royal purple its like $9 a quart but its dyno proven to get you a extra 2 HP. It is the best oil out there hands down. but right now to top it off i would put that syn blend or what ever half conventional and half synthetic because you don't know whats in there before and it blends very nice with both.

Synthetic oil looks, and smells just like regular dino juice. Synthetic oil is "slicker" than regular oil, therefore it cleans the engine, which could be a problem if you've got an older engine with a lot of miles on it, kinda like changing the transmission fluid and filter in a tranny that's never had a service job done to it. You might run into problems because it'll get all the gunk that's in there out and could cause some problems simply because synthetic oil will actually "clean out" the crud that's in there. My recommendation, do it, but make sure you try to run a good engine flush through the motor before it gets changed. Filter construction still relegates you to about 3000 miles between changes, meanwhile the oil technology can give you up to 15,000 miles before it starts to lose its lubricating properties.

Yeah, I was planning on flushing the engine out. We did that to the Prizm since it had early stages of sludge buildup. For now I'm going to add Citgo 5W30 oil, just so it has enough. It really is on teh low side...I'm not sure why since I can't find any leaks...but I've read of the 2.7L going through oil faster than usual.

Well I called the dealership today that serviced the car for the previous owner. They told me it''s got regular oil in it, so today I added 2 quarts of Citgo 5W30 oil (is Citgo a pretty good oil brand?). I also asked if the car had any major issues and they told me that they never had any real problems with the car and that she took good care of it. That makes me feel good, but it also makes me want to get synthetic oil in their relatively soon.

Well I called the dealership today that serviced the car for the previous owner. They told me it''s got regular oil in it, so today I added 2 quarts of Citgo 5W30 oil (is Citgo a pretty good oil brand?). I also asked if the car had any major issues and they told me that they never had any real problems with the car and that she took good care of it. That makes me feel good, but it also makes me want to get synthetic oil in their relatively soon.

Any dino (regular) oil will do fine for now. Regular oils are pretty much the same.....

Flushing it would be a good idea....

The only thing you will have to keep an eye on will be your gasket seals....though they are pretty easy to replace, and the protection that synthetic offers will be more than worth it in the long run.

Yeah, I was planning on flushing the engine out. We did that to the Prizm since it had early stages of sludge buildup. For now I'm going to add Citgo 5W30 oil, just so it has enough. It really is on teh low side...I'm not sure why since I can't find any leaks...but I've read of the 2.7L going through oil faster than usual.

Been idling/ city driving a lot lately?

Synthetic is all ways a good idea no matter what the age of the car, make sure you change the oil filter too. If the car has alot of miles and you dont want to go to synthetic right now 10W30 might be a good idea.

if you have mad cash run royal purple its like $9 a quart but its dyno proven to get you a extra 2 HP.

and if my grandmother had wheels, she'd be a wagon.

Actually, I have see an article that supported that also; they changed all dino fluids for synthetics (engine, trans, axle) and did pick up a few measurable HP. Not enought to bother draining everything one Saturday, but if you were rebuilding a car from scratch, it's worth considering, IMO.

Actually, I have see an article that supported that also; they changed all dino fluids for synthetics (engine, trans, axle) and did pick up a few measurable HP. Not enought to bother draining everything one Saturday, but if you were rebuilding a car from scratch, it's worth considering, IMO.

Or if you are a die-hard.

Heck, if you drive hard, it's worth considering.

If I decide to take the other car auto-Xing, all the fluids will be replaced with synthetics. This way it can still be driven normally,

but abused on the weekends...

It all depends on how you drive it...

Synthetic is all ways a good idea no matter what the age of the car, make sure you change the oil filter too. If the car has alot of miles and you dont want to go to synthetic right now 10W30 might be a good idea.

It's got 175k miles on it.

Just switch to Mobil 1. Safe & smart decision.

and if my grandmother had wheels, she'd be a wagon.

Really Royal Purple is no joke. We use there oils for our machines at the shop its F'in expensive for a couple 55 gallon drums. but nothing lasts as long or lubes better. It passes water/oil Stress tests and stuff Mobil one hasn't come close yet to Royal purple. but a while back i Think Hot Rod magazine did the test to prove there claim. AS a average driver though you wont notice anything.

Do I use it. Rarely. plus they way i burn oil in the caprice I coulnd afford it.

I can't see myself paying 50 bucks plus for oil though...