Another "Oil Change Interval" Thread

[RadarRider]

We've seen our fair share of "what oils to use" & "oil change interval" threads, but something incredible's been happening all summer with my rig & I've come to a conclusion: I think I'm going to change my oil every 7000-9000mi.

@ just the very end of winter, somewhere around Feb., I had been so busy with work that I didn't have too much time to keep up on regular maint. The 2 things I absolutely worried about the most were of course, the fuel filter & the oil. We all know the fuel filter's the cheapest & quickest item for routine maint. I had run down to NAPA, paid the $12, drained the fuel bowl, & dropped in the new filter. No problems. As for the oil though, I didn't have a choice. I had to push it as far as it would go.

Keep in mind; I don't have any fancy remote oil filters like the FS2500 or whatever else there is on the market. All I use is a NAPA or Motorcraft oil filter & some good ol' Rotella.

So from the end of Feb to about a few weeks ago, I had been driving back & forth to work, picking my son up from CT(75mi 1-way, 150mi round trip, 300mi pick up & drop off), & driving up to NH(trips range from 100 to 410mi.). Within this entire period, I didn't have one single problem with performance, I only had to top the oil off once(about 3 1/2qts.), & I was consistently getting 18-19mpg on the longer trips. I've monitored Heavy's performance, maint. costs, etc. & this year has been THE best in cost efficiency, MPG, & overall performance when I needed it!

I use a Motorcraft box top from the 1st filter I bought from Heavy as kind of a log for oil & fuel filter changes. All I write down is the date & mileage to keep track of the next oil change which used to be 5k mi. I finally got some time to get the oil & filter for what I thought was a long over due oil change a little over a month ago. I looked @ the box top & the last time Heavy had an oil change was 115,877 on 11/2/09. The mileage @ the oil change was 124,999. For all of us that aren't math whizzes, that's 9122mi!!!


So now I've decided, since I can push my Rotella(one of the best brands IMO), this far, I've got faith in my 7.3 & Rotella so much that I'm going to extend the oil changes between 7k to 9k, depending on when I pay attention to the odometer.

Who else has "the faith"?

[mas360]

No, I have no faith and just changed mine last night after 3500 miles. Better safe than sorry. It is cheap relative to engine repair cost....)

[Dietoremain]

The only way your post would be able to be backed up is have that oil analyzed. and i honestly dont think it lasts near that long at the right level. i change mine every 4k max. I may be able to go 5k but I choose not to. and even people getting analysis on dyno oil are changing every 5-6k max.

[symbols]

I'm thinking a $25 oil analysis is cheap insurance and well worth it

[RadarRider]

Originally Posted by mas360

No, I have no faith and just changed mine last night after 3500 miles. Better safe than sorry. It is cheap relative to engine repair cost....)

Originally Posted by Dietoremain

The only way your post would be able to be backed up is have that oil analyzed. and i honestly dont think it lasts near that long at the right level. i change mine every 4k max. I may be able to go 5k but I choose not to. and even people getting analysis on dyno oil are changing every 5-6k max.

Originally Posted by symbols

I'm thinking a $25 oil analysis is cheap insurance and well worth it

I can see what you guys are saying, but being around diesels for a good part of my life, I can't 100% agree. In my last job, I was a drill rig technician & the company I worked for also rented out hydraulic vibratory hammers that ran off of various Cat engines. They also have 2 F-550 maintenance trucks, both with 7.3s that were constantly on the road. The company did a great job of servicing & repairing these machines & trucks, but the machines that were on rental for extended intervals in places that were out in the middle of nowhere that weren't exactly ideal spots for oil changes & worked continuously. There were some drill rigs(the smallest ones having 5.9l Cummins), & even some of the hyd hammers that were either bought or rented out that ran day & night.

As for the F-550s, there were times one of the other techs would be out on the road for weeks, come back for some R&R, & go back out anywhere in the country & the oil change would be overdue upwards of 12k mi. On top of this, most of the jobs you had to do to work on the machines would require using the PTOs for the air comp(that ran 1/2" & 3/4" air lines) which kept the trucks running for hours on end.

The proofs right there. With all the additives & detergents in oil nowadays, it just isn't the same as it was even 10yrs. ago, it's much better & keeps improving. Even with straight-based petroleum oils & their break down rates, I do not see a problem going up to 9k mi. I wouldn't go so far as to try 12k or more, but if it happens, it happens.

Oil analysis? C'mon, you guys. Really, are we driving diesels or what? I understand the HEUI system can be sensitive as far as dirty oil reaching the injectors, but don't forget what these trucks were designed to do. There are Super Duties out there that live a far harsher life than your trucks & they still start up 1st shot. Might huff 'n puff a little, but they'll still do what they were made to do.

[symbols]

Well it's your truck you can treat it like you want. All I'm saying is it only costs $25 to have the oil analyzed so what is the harm in having it checked at 7k miles? Just because the engine is still running with old oil in it doesn't mean it's not causing damage.

[RadarRider]

Originally Posted by symbols

Well it's your truck you can treat it like you want. All I'm saying is it only costs $25 to have the oil analyzed so what is the harm in having it checked at 7k miles? Just because the engine is still running with old oil in it doesn't mean it's not causing damage.

In all due respect, Jay, what kind of damage are we talking about here? Don't forget about the crap that gets accumulated through the fuel bowl & intake & also the scale that's running through our water jackets in the cooling system that, no matter how much you get your system flushed, is still floating in our antifreeze. & you won't ever be able to get that stuff out unless you started pulling your fuel bowl/system apart or the turbo & exhaust. It's all normal wear & tear. Like I've said, what's 9k mi.? Like I've also said, I honestly wouldn't push it over 10k., but if I did, what's 1 time? I could understand if I ran my truck a little harder or constantly pulled a load, but this is all highway miles with an empty truck we're talking about here. It's never been run hot, the heaviest it's pulled was less than 2000lbs., & the hardest it works is in the winter when it's in 4x4.

[symbols]

I'm not saying you shouldn't do it or that it's a bad idea. All I'm saying is if your gonna try and extend your oil change intervals what's $25 for peace of mind? Once you figure out how long you can safely extend your intervals and your driving habits don't change then you can safely do it all the time without worrying if your causing any damage.

I have a neighbor that asked me to come look at his car because it stopped running. After looking at it I found out he had NEVER changed the oil So he basically got 50k miles out of his oil but in the long run it cost him a lot more than he saved.

What I'm saying is at some point the oil stops doing it's job and it's to your benefit (especially when it's so cheap) to know when your oil is no longer doing it's job.

[RadarRider]

Originally Posted by symbols

I'm not saying you shouldn't do it or that it's a bad idea. All I'm saying is if your gonna try and extend your oil change intervals what's $25 for peace of mind? Once you figure out how long you can safely extend your intervals and your driving habits don't change then you can safely do it all the time without worrying if your causing any damage.

I have a neighbor that asked me to come look at his car because it stopped running. After looking at it I found out he had NEVER changed the oil So he basically got 50k miles out of his oil but in the long run it cost him a lot more than he saved.

What I'm saying is at some point the oil stops doing it's job and it's to your benefit (especially when it's so cheap) to know when your oil is no longer doing it's job.

Agreed. I'll give it a shot.

[mas360]

I don't know how long you want to keep your SuperDuty running. I plan to keep mine to 500K, so, oil change at every 5K and transmission fluid change every 30K is a cheap insurance....