As a rule of thumb, in used vehicle, I will run a synthetic blend for the first oil change and change it at at 1500 miles. This should gradually start to break down any deposits and sludge that may be in there. Then I'll go to a 100% full synthetic with a 3000 mile change after which I will go to 6000 miles between changes.

I don't know if there is any proven facts that show an advantage to this over a straight swap to synthetic, but I kinda think it's best to "ease" into the change, especially with a higher mileage (50-60k or more) engine that I know had been using conventional oil or at least I can't verify the use of synthetics.

To my line of thinkin', you really don't want to break gunk down too fast. It needs to be a gradual break down of contaminants so as not to clog up the filter or sending unit, which will give you a problem. It's not real common, but you'll read the occasional post that states, "I switched to synthetic oil and blew my engine"! Well it's not the switch, but the fact that the sludge and deposits were taken into the oil too quickly, at least IMO.
First time I put Royal Purple in the Jeep it was dirty at change time and that was at 3000 miles. Now I go 6000 miles which is about 6 months for me and it comes out clean enough to easily read the dip stich letters thru it.
Now with an '08, I don't think any buildup would be that bad. The swap to synthetic would cause an issue at all. If you think it's already getting a bit too dirty for your liking, then change it at half your normal interval until it appears to be cleaner.

One additional note, as a rule, modern oils, especially synthetics, hold up longer than filters. If you plan on extending the change intervals to offset the higher cost of the oil (my RP is running at about $8 a quart and I use 6 in the Jeep and 7 in the truck), then either change the filter at 3k and top off the oil, or use a very high quality filter...

 

What he said^^^ But I would add one more tid bit of Info. When the vehicle is worked above normal driving habits, then the intervals should be cut in half. imo.

 

As my experience with working on heavy equipment and a 07 hemi owner currently running m1 full syn, biggest thing is to keep your eyes glued on the oil pressure gauge. I have lost 1 engine in my 73 beetle to a loss of oil pressure. (Thats what I get for running a used bottom end without splitting the case and taking a good look inside first!) If your that concerned you can find an oil lab and have your oil tested, or at least partical counted. I currently run mobile 1 5w20 with 1 quart of pure syn lucas. The only problem so far is I keep getting a code for incorrect engine oil type. Well along with others but none that have been affected with just oil. (Evap leak, o2 sensor heater circuit high, multi cyl misfire...) I work for caterpillar and we partical count our suspect oils first before getting a full analysis done. But you shouldnt have any problems as far as just switching. As for running "clean out" additives, there I would get a little weary. Some say you can fix low oi pressure by adding a little bit of saw dust. But the fact remain by that point the damage is already done and it needs some real tlc. So I personally wouldnt put anything in my oil to help break it down. Just a religious change period and you should be good to go with the almighty important daily checks. Bottom line, if you dont like the way it looks change it. Oil is cheap insurance when it comes between changing oil or rebuilding/ replacing the entire engine. Not saying im 100% correct but just simply adding my $0.02. Feel free to correct me if im wrong. Its the only way we learn. Well that and asking questions!

 

Is there a filter that last longer than 3k? I know the filter is cheap because a friend that works in a garage let me come in because I wanted to get under there and see how they ran my exhaust. I forget which filter it is but it's not a high end filter. So I will do what y'all suggested and change it at 3000 miles. Any recommendeation's?

 

Mobil 1, K&N, Purolator Pure one filters all have Synthetic media fibers in them and are the better ranked filters. I wouldnt go more than 5kmi on any filter personally, but one of those you can sneak away with 7500 miles granted the majority of your oil is clean.

 

I'll be changing oil every 5000. It's what my friend suggested and what the garage that I went to wrote down on my sticker. I'm sure I could go longer but 5000 is nice and even number to remember. I like the mobile 1 but my understanding is it's the champ rebranded but it's not the e-core. Puralators have good reviews to. That and Wix. Seems there is only a few filter manufactures out there so it's no surprise.

 

Since we are talking about oils here, what type are you guys using? I see they recommend 5W20 in the Hemi's. Is that what you fellas are sticking with? Thanks, and sorry about the thread jack...

 

If I'm not mistaken 5w20 is a must in Hemis with the MDS. Other than that any brand oil today will be fine as long as the proper maintenance intervals are upheld. Pennzoil, Valvoline, Mobil, Castrol, they'll all do the job just fine.

Do some perform better than others? Sure, some engines are picky and respond better to PP instead of M1. Doesn't mean that M1 is a bad oil it just means that, that specific vehicle runs better on PP. Meanwhile you could take another vehicle and you'll find that it likes M1 better than PP. Brand of oil simply isn't as important as many people try to make it, as long as they are API certified and they meet manufacturers recommendations you'll be fine.

IMO the most important thing about using the right oil is being honest with yourself and recognizing the kind of stresses you put your engine through and deciding what interval would be best for those conditions. Once you've figured that out and you know what oils on paper would be good for those conditions then find the oil that makes you enjoy the way your truck feels the most and stick with it.

O and to answer your question. Right now its got M1 but next change will be Valvoline SynPower.

 

Mobil 1 is good stuff. I either run that or amsoil if i can afford it.
typicaly the 1st oil change after a switch to syth the oil is very dark and should be changed well before the normal time. Give it some miles to clean out then change. i would say 2500-3000 mi

 

Alright, thank ya.

Yeah, I got the maintenance thing down, I was just wondering if I should use 5w20 or something else... sounds like it really doesn't matter.

I have ran 10w30 Valvoline Durablend through my 2nd gen for every bit of the 165k miles on it, changed it every 3000k miles (sometimes sooner, religiously) and haven't had an issue yet. But I'm thinking about going to full synthetic with the hemi. I suppose I will use the the 5w20... just didn't know if that was what everybody else was doing or if it was kinda mandatory.