Question regarding oil interval changes

[jcmseven]

Fellow Posters:

I have a 2002 Ford Powerstroke 7.3L which I switched to synthetic oil at the last oil change. I have never done an oil analysis, and due to my schedule, might not get around to it. I put Mobil 1 synthetic oil (diesel compatable) 5-40 in the truck at 47,000 miles after running Rotella conventional to that point. I now have 52,000 roughly on the truck and am wondering about how long I should wait before changing. In the past I have gone 6000-7000 miles between changes with no problems. I do mostly local driving to and from work. The truck is started generally just twice daily and the drive is 17 miles round trip. It appears to reach operating temp before it is shut off. I did notice an increased comsumption of oil after changing, but that has slowed of late. I have added two additional quarts this change, where before I rarely added any. My fuel consumption has decreased on average about 1 mpg. Also, how often do I change the fuel filter? The book says every 15000 miles, but if I run a cetane booster/additive, do I need to do it that often? I have been religious about changing them, but it has seemed to me they might not need changing so often. Your advice is appreciated.

John M

 

[JerryG]

John,
If you want to use Mobil 1, I would suggest using the Mobil 1 Truck and SUV oil. It is the exact same oil as Mobil 1 Delvac heavy duty diesel oil. The regular Mobil 1 is diesel rated, but is not rated for heavy duty diesel use.

 

[HGM]

John,
I dont think you can go wrong with synthetic. Though, most folks here know that I dont believe its needed in the crankcase.. My personal opinion it that its a waste of money(take it how you will).. Either way, as has been discussed her on many ocasions, keep the same intervals.. 5-7000mi depending on severity of driving(I think your's is severe because of lack of run time) or 200hrs.. Your P/S has HUEI injectors, meaning the injectors are fired by the engine oil. If your oil is contaminated, aerated, or of the wrong viscosity it will effect your drivability(lack of power,run rough,missfire,poor fuel economy,etc).. There are many P/S diesels running out there with over 600,000mi on regular bulk 15W40 Motorcraft dino oil.. If you keep the air filter(no aftermarket filters other than the HD Ford replacement filter) and fuel filter replaced(15k is a good idea, again factory only) with good fuel(recomend fuel additives) you will recieve a long life and reliability from your P/S..Sorry, diesels arent cheap, but they will last much longer than any gas engine if taken care of..

 

[jcmseven]

Greg,

If the oil change intervals are the same, and I do not heavily use my pickup, except on occasion, am I just as well to go back to conventional oil such as Rotella?? Would that cause any harm to the engine, to switch back??? It certainly would be easier to do conventional oil, but I want to offer maximal protection. The slight gain in fuel economy that I have noted with the syn oil is not that big a deal to me.

John M

 

[HGM]

</font><font color="blue" class="small">( Greg,

If the oil change intervals are the same, and I do not heavily use my pickup, except on occasion, am I just as well to go back to conventional oil such as Rotella?? Would that cause any harm to the engine, to switch back??? It certainly would be easier to do conventional oil, but I want to offer maximal protection. The slight gain in fuel economy that I have noted with the syn oil is not that big a deal to me.

John M )</font>

In my opinion, yes... There are some guys here that run syn in everything, again its not a bad idea just not necessary.. Engine oil is one fluid that must be changed frequently due to contamination, so you dont get the benefits of extended life from the syn.

Personally, I would look at Rotella and Motorcraft and simply use the cheaper.. The engine was designed to run on Motorcraft, and I have had good luck with it..there have been rare instances where we have seen drivability issues while runing Rotella or Dello and a simple change to Motorcraft fixed it.. Basicly, if Rotella works for you that will be fine..

 

[dmccarty]

John,

I have a 2002 Ford 7.3 as well. I run the Shell synthetic 5w40 in mine. I do this for a couple reasons. One its hard for me to just stop everything I'm doing and change the oil when 5,000 miles are up. I aim to change at 5,000 but I have gone just shy of 8,000 miles without a problem. The oil analysis says to try to go to 9,000. I run about 70 miles round trip a day so I rack up the miles pretty quick. My milage is mostly rural with a bit of city mixed in.

I do see a bit better milage but not enough to soley justify the extra dollars for the synthetic but it helps. Another biggy for me to use synthetic is cold weather starting. While we don't get real cold the engine sounds a heck of a lot better when its started and the temps are in the low 20s.

I think one needs to change the fuel filter at or below 15,000 miles. I think these engines are senstive to fuel quality. Its not worth messing with. I change the air filter on schedule or maybe a bit before. Lately I have been getting my filters from my JD dealer. JD sells Fleetguard filters. I can order it from my dealer and they send it to my house. I usually get in the next day after the order. Some of their prices have been higher compared to buying at the store but sometimes they are lower. The net is the same. AND I don't have to stop at the store to find out they dont have the filter I need which seems to happen frequently. /forums/images/graemlins/frown.gif

My concern with your driving is that you said you are going 17 local miles round trip. If local means city then you should be changing the oil sooner. I had one sample come back that had fuel in the oil. It was barely within spec but it turned out to be the heavy traffic and idle times I had on that oil. If you are doing 8-9 miles one way I would be concerned if the truck is warming up enough. Seems like my temp gage takes at least 4-5 miles to come up when its cold out.

You might want to spend $30 to get the oil tested. Get the TBN tested as well. They might tell you that you need to change more often then 5,000 miles and if that is true running synthetic might not make sense.

Later,
Dan

 

[RalphVa]

I've doubled my oil change intervals on all my vehicles since changing to Mobil 1. In my case, this is 6,000 miles vs. 3,000 miles. Do the math, with 3-4% mileage improvement and doubling the interval, Mobil 1 pays for itself.

The new Benz's with Mobil 1 (gas engines) recommended change interval is 15,000 miles. The dealers tell people 12,000 miles to get them in by the 15k mark. Don't know what they say on their one diesel model (the E320). You might call a Benz dealer and see what they say about the E320 diesel change interval with Mobil 1.

If I go on trips, etc. I used to change at 5k. Now, I'll let it go to 10k if I happen to take a long trip. This is on 2 gas-engined vehicles and 1 diesel with 195k miles on it.

The diesel is the only one that uses oil and has always used about a quart every 2k miles. Think that's approximately what it's using still with Mobil 1, possibly a bit more. On the second Mobil 1 change, I went with the new 5w40 "SUV" oil. Can't seem to find it now. Hope they have it available again locally when I need to change it about the end of the summer.

On my Gravely, its oil comsumption went up when I switched to Mobil 1 but then went down with the second Mobil 1 change.

I'd keep the filter change to 15k miles. See no reason to change that.

Ralph

 

[kenmac]

Any group 4 (or better) synthetic diesel rated oil will be a good oil (better than dino). That said,I wouldn't run the synthetic oil or any oil past the vehicle manufacture specs. without an oil analysis to determind what's going on in the engine as far as wear metals, soot ,contamination, tbn loss, etc, & the breaking down of the oil adds.in general.