Since your in Kentucky, and the temps aren't very extreme, either a 5w-30 or 10w-30 would be sufficent. The difference between Amsoil's SAE 5w-30 and their SAE 10w-30 is that the 5w is rated to pour at -60 degrees F. where as the 10w-30 is only rated to pour at -54 (not much of a difference). This is known as the low temperature kinematic vicosity. Both are technically a 30 weight oil , think of the first number with the W as the "winter rating". The 5w-30 has more viscosity index improvers than the 10w-30. These VIIs minimize thinning of the oil as the temperatures increase. This allows the lighter base stocks to now also meet the higher temperature requirements. A simple description to decribe these types of oils is their common name, "multi-grade" oils.


Bill,

 

Bill,
I own a 2000 Durango and I'm waiting for my '04 Dakota to arrive from the factory. I'm currently running regular motor oil in the Durango. Is there any problems associated with switching from regular to synthetic? Is there any particular procedure necessary to switch, like flushing the old oil before adding the synthetic stuff?

Thanks,
Jeff

 

"A motor oil can only clean the first layer of contamination" - Terry Dyson http://www.bobistheoilguy.com/terry.html

"Flush" is perhaps an overused and misunderstood term. I prefer the term: "cleaning", or more precisely "internal engine oil system cleaning". A clean engine allows the oil to do the intended job.

Solvent Flushes - Some engine flush products and systems can be harmful to your engine and really don't clean as well as advertised. I will not comment on the various machines and proprietary solvents used at lube centers and some auto repair shops other than the idea of aromatic solvent under pressure flowing through an engine does not appeal to me. Solvent under pressure could potentially dislodge large chunks of deposits, clogging passages with little chance of further dissolving. There is also concern with this pressure on seals. The solvent products used only under idle conditions are generally safer than the pressure flushes, but under NO circumstances would I recommend driving with these solvent products or diesel fuel, ATF, or other "cleaning product" in the crankcase that severely dilutes, thins and shears motor oil. Lastly there is always the question of how much solvent remains. This is certainly a concern. Always allow a long drain period to allow the diluted oil to run out (which it should readily do) but also allow the aromatics to evaporate from the warm engine opened engine. Following a treatment with a good solvent cleaning, I recommend a short oil change interval. AMSOIL engine flush is an idle only product that is not harmful but does fall short in the actual cleaning performance. AMSOIL engine flush is simply poured into the crankcase (after installing a NEW oil filter), the engine is idled 15 minutes, shut down, then drained for as long as possible with filter removed.

Tear down and clean - This would be good if you could, but it usually requires a few weekends, some big cash, some thick books, many years of knowledge and maybe a little intestinal fortitude. Usually advised only if you have a mechanical problem, a problem that requires tear down anyway. Not practical for your otherwise fine running Volvo turbo, Lexus or Suburban.

Synthetic oil cleaning- Synthetic oil alone will clean some areas of your engine, some areas where oil pools and even some oil galleys will be cleaned a bit with synthetic oil alone. Some issues with this, the cleaning will be slow at best, and even though it may not sound logical - this cleaned contamination will be put into suspension in your oil and reduce the time you can use the oil via contamination. Another issue, is that some areas just will not be cleaned with the oil alone. A good example are the ring grooves and the surfaces of the rings.

Additive cleaning- This is a new area of engine cleaning. Most of the chemistry is relatively new, but don't let that scare you, because A) it is very safe B) the ester based compounds are natural. I highly recommend a product called Auto-Rx® . The usage instructions, which are updated periodically on the Auto-Rx® web page, are subdivided somewhat logically into low/high mileage treatment categories. This makes sense because cars with more miles will have a tendency to have dirtier engines, but car and engine type, driving style, maintenance routines, oil variety also play large roles in how much dirt and sludge will be built up. A car with under 50,000 miles of stop and go driving with petroleum oil changed at 8,000 mile intervals (if the owner remembers) could have a sludge problem that needs cleaning.

So why clean your engine?

If you are switching over to synthetic oil, some of the benefits will become much more apparent if you start with a clean engine. Longer oil change intervals, better cooling, more power are just a couple key characteristics that are enhanced if old petroleum oil residues are removed. Just changing to any synthetic oil will not completely clean your engine - honestly I used to think this - but there are just some locations in the engine that oil won't clean. Auto-Rx® will clean these areas and allow the synthetic oil to keep the rings free floating, thus allowing a better compression seal and result in more power and less emissions, for example.

If you start with a seriously clean engine your oil will last longer and frankly will protect the engine better. Many of the deposits and crud, and especially the more harmful by-products of petroleum oil oxidation tend to have an acidic reaction. This will deplete the additives in any motor oil.




No problems associated with switching to synthetic after running petroleum oil. The high detergency of synthetic oil will occasionally clean the sludge (that is acting as a band-aid) on an already bad seal causing an oil leak. I switched my Ram to Amsoil at 125,000 miles.

I hope this answered your questions

 

Thanks Bill!
Wow, if you ask a question on this forum, you better be ready for the answer! So let me paraphrase: With 35, 000 miles on the Durango, I should use Auto-RX to clean some of the junk out of it before I switch to synthetic oil and when my Dakota gets here with relatively few miles on it, it should be safe to go right to the synthetic but use a shorter interval between the first and second oil change, right?
I have to admit that I considered using synrthetic oil in the Durango when we bought it new but the price of the synthetic stuff scared me away from using it. Not that we're having any engine-related problems with the Durango, it just makes sense to protect and prolong the life of something that cost so much to purchase in the first place.
One more question: Where can I get the Auto-RX? I can't remember seeing it on the shelves at Wally-World. Is it an everyday product or do I have to special order it? Sorry, I guess that's two...just put it on my tab, please...

Hope you're having a great day!
Jeff

 

With 35,000 miles, you probably won't need to do an Auto-rx treatment. Auto-Rx would work but, it is better suited to poorly maintained,or engines prone to sludge issues. You would be safe and money ahead if you used a safe "quick-flush" like Amsoil's engine flush. It costs less than $5 total. Here is the link to ARX www.auto-rx.com .

Synthetic oil is only cost prohibitive if you change it every 3 to 5000 miles. You can safely run a good synthetic oil 8000 miles or more. In my trucks, I replaced the oil filters at 6 months and the oil at 1 year. Total miles for my Ram was about 8500 and 1 year and for my Dakota, 16,400 / 1yr.

 

Save money? Sounds good to me! I'll go for the Amsoil.
Thanks again for the info. I really appreciate it.

Jeff

By the way, my Dakote should be here in 3 weeks according to the dealer. Know anyone looking for a pretty black Ram? I've got it listed in the classified section on this forum. Hopefully someone will pick up this clean ride. I hate to get rid of it but it doesn't fit too well in my garage...