C7 Oil Consumption

[1ciderdog]

Originally Posted by gatorcq

9K for oil change is way too long. CAT recommends 1000gal of fuel burn or 6000miles.

CAT has the HEUI pump, clean oil is critical.

The way I read it the recommended change is 1100 gallons not 1000 gallons. I've tracked the fuel mileage on my C-7 for over 67,000 miles. The lifetime average is 7.8 mpg. Using 7.8 for a 1100 gallons usage service is 8580 miles. My actual mileage between the change mentioned above in post 4 was 8495 but I wrote it as about 9K. I agree changing the oil & filter often is the best practice.

[mel s]

Originally Posted by gatorcq

9K for oil change is way too long. CAT recommends 1000gal of fuel burn or 6000miles.

CAT has the HEUI pump, clean oil is critical.

gatorcq
That is a good point.
However the question is "When is the oil to dirty to continue to use"?

Is that 1000gal/6000 mile recommendation for the 3126 engine?
Where do you find it?

The question for which I have not found a "definitive" answer is: "When does Cat recommend the oil in my 3126 be changed"?

The available Cat published/printed recommendations are "all over the map", (they vary from "every 9,200 miles" to "every 16,800 miles" for my 3126), depending upon which publication I read.

BTW, even the Cat "help line" can't/won't answer that question with any certainty.....(IMO, "every year, before you put away for storage"is not a very good answer).
I haven't stored my coach for 10 years.
I use it occasionally for 8 or 9 months a year and travel often for 3-4 months each winter in the south and southwest, overnighting for a day here and there, camping for 2-5 days in a row, (sometimes camping for as long as a month in one place).

In the 12 years I have owned my coach I have driven it as little as 2,000 a year.... and other years 12,000+.

I find it odd that Cat won't/can't tell me the best oil change interval.... auto manufactures have never had a problem specifying "exact oil change intervals".

Mel
'96 250hp 3126 cat, 132k miles

[1ciderdog]

This one covers the C7 & C9 so it may not be appropriate for your 3126. http://safety.cat.com/cda/files/2453...083-09%20M.pdf

but this one covers the 3126. http://safety.cat.com/cda/files/572649/7/3126B

Interesting oil change is 1000 hours for the 3126B and 1100 hours for the C-7.

[mel s]

Originally Posted by 1ciderdog

This one covers the 3126. http://safety.cat.com/cda/files/572649/7/3126B

1ciderdog
Interesting, hopefully that pdf applies to the 3126 Cat as well, (I have not been able to find a similar document that applies specifically to the earlier 3126, which is what powers my Safari).

According to that pdf, a "vehicle" powered by a 3126B Cat engine, when using 28 quarts per change, can be driven as many as 16,800 miles between oil changes.

Table 22, on page 179, titled "Maximum” Permissible Oil Change Interval", shows that the Caterpillar recommended oil change intervals are as follows:
1.) 16,800 miles, if/when used for "Light Duty" service
2.) 14,000 miles, if/when used for "Medium Duty" service
3.) 11,200 miles, if/when used for "Heavy Duty" Service
4.) 9,200 miles, if/when used for "Severe" service

Since MHs are usually heavily loaded, (especially when towing) I assume that either the oil change interval for "heavy duty service" or "severe service" would apply.
The way I read it, I should change my oil between 9,200 and 11,200 miles.

Thanks!
Mel
'96 Safari, 250hp 3126 Cat

[Old Scout]

MH use is considered heavy or severe use--you are kidding, right? Semis, garbage trucks or off road but not MHs.....10 or 12k miles or once a year, preferrably before storage is about right for me----oops I own a Cummins--nevermind....
PS--3-4 qrts per 10k miles is probably about right...

[mel s]

Originally Posted by Old Scout

MH use is considered heavy or severe use--you are kidding, right? Semis, garbage trucks or off road but not MHs.....10 or 12k miles or once a year, preferrably before storage is about right for me----oops I own a Cummins--nevermind....
PS--3-4 qrts per 10k miles is probably about right...

Old Scout
Thanks
Isn't driving a fully loaded MH, dragging a toad all, over this country for 10-12,000 miles each year pretty much the same as driving dump truck, full of gravel, for the same number of miles?
Is that "Light Duty", "Medium Duty", or Heavy Duty" service?

I have heard that "before storage" is the "preferred" time to change my oil.
Since I never really "store" my coach I have not been able to figure out when the best time to change my oil might be!

Is it prior to one of the the 5-6 times a year that I may not drive it for 3-4 week periods in in the warmer, (spring/summer/fall), months ?

Or is it prior to a month I may spend in a RV park in a southern state during Jan., Feb. or March?

Or maybe the best time would be half way to wherever I might be going sometime?

So many question so little time!
This nomadic life style is not without it's challenges!

Thanks again.

Mel
'96 Safari, moving again on Aug. 24th, (only 250 miles, this time)

[mel s]

Originally Posted by Old Scout

MH use is considered heavy or severe use--you are kidding, right? Semis, garbage trucks or off road but not MHs.....10 or 12k miles or once a year, preferrably before storage is about right for me----oops I own a Cummins--nevermind....
PS--3-4 qrts per 10k miles is probably about right...

Old Scout
Update:
After studying the Caterpillar publication "3126B TRUCK ENGINES Maintenance Intervals" pdf:
http://safety.cat.com/cda/files/572649/7/3126B
I have discovered the following:
1.) A vehicle powered by a 3126B engine, (with the 28 quart oil capacity), if averaging 8-10 MPG, is considered by Cat as seeing "medium duty" service...(10-12 MPG = "light duty" service).
2.) A vehicle powered by a 3126B Cat engine, (with the 28 quart oil capacity), seeing "medium duty" service can safely be driven 14,000 between oil changes....
(If seeing "light duty" service, 16,800 miles).
Mel
'96 Sahara, 250hp 3126 Cat, (8.5 MPG)

[sevenmacs]

Originally Posted by mrock

Just completed 10,000 mile trip coast to coast as well as East coast trip. Consumed 8 quarts of oil in our 350HP CAT C7. Would this be considered excessive oil consumption? Genset 7.5 ONAN used half quart for 600 hours used. Thanks

I'd say too much consumption, I agree that it probably went out slobber tube due to overfilling. I used the dipstick calibration method when I changed my oil the first time. In the first couple thousand miles it blew out 2 qts and went back to original level mark on dipstick. Now that's where I fill to and doesn't use much after that, maybe a qt between changes.

[mel s]

Originally Posted by sevenmacs

I'd say too much consumption, I agree that it probably went out slobber tube due to overfilling. I used the dipstick calibration method when I changed my oil the first time. In the first couple thousand miles it blew out 2 qts and went back to original level mark on dipstick. Now that's where I fill to and doesn't use much after that, maybe a qt between changes.

sevenmacs
I agree,
Since I have been filling my crankcase with the "Cat recommended quantity of oil", for the last 10-12 oil changes I've also used "maybe a qt between changes".
Mel
'96 Safari, 3126 cat, (132k miles)

[rvjimmy]

Originally Posted by mel stuplich

Old Scout
Thanks
Isn't driving a fully loaded MH, dragging a toad all, over this country for 10-12,000 miles each year pretty much the same as driving dump truck, full of gravel, for the same number of miles?
Is that "Light Duty", "Medium Duty", or Heavy Duty" service?

I have heard that "before storage" is the "preferred" time to change my oil.
Since I never really "store" my coach I have not been able to figure out when the best time to change my oil might be!

Is it prior to one of the the 5-6 times a year that I may not drive it for 3-4 week periods in in the warmer, (spring/summer/fall), months ?

Or is it prior to a month I may spend in a RV park in a southern state during Jan., Feb. or March?

Or maybe the best time would be half way to wherever I might be going sometime?

So many question so little time!
This nomadic life style is not without it's challenges!

Thanks again.

Mel
'96 Safari, moving again on Aug. 24th, (only 250 miles, this time)

What you are saying is your rig weighs 73,280 pounds, sound like you might want to lighten up a little, maybe. Jim

[mel s]

Originally Posted by rvjimmy

What you are saying is your rig weighs 73,280 pounds, sound like you might want to lighten up a little, maybe. Jim

rvjimmy
I did lighten "up a litttle", when I did I posted an UPDATE....(3days ago)!
See message #21 of this thread
Mel

[jauguston]

jimmy,

It doesn't really matter when you do your oil change. Its best to have the engine well warmed up when you do it. Oil is not expensive and I would not try to extend the change interval to the maximum Cat says is allowed. The fuel injection system relies on clean oil for the system to operate properly. You can buy a lot of oil for what a failed HEUI system could cost and there is a direct link between dirty heavy oil and HEUI/injector failure.

Jim

[gatorcq]

Called CAT, max fuel burn is 1000 gals. Since oil is a key component to a CAT engine (HEUI, injectors). I plan on increasing my oil change frwequency. Currently max 6000 miles, going to 5K. I figure $80, for me to do it or $170 for Speedco (Oil, Fuel, Lub). Is a good investment for my engine.

[mel s]

Originally Posted by gatorcq

Called CAT, max fuel burn is 1000 gals. Since oil is a key component to a CAT engine (HEUI, injectors). I plan on increasing my oil change frwequency. Currently max 6000 miles, going to 5K. I figure $80, for me to do it or $170 for Speedco (Oil, Fuel, Lub). Is a good investment for my engine.

My coach will travel between 8,000 and 8,500 miles on 1,000 gal of diesel.
I have never exceed 8,500 miles, (usually 6,000), between an oil and filter change, (fuel filters also).
IMO, every 5,000 is overkill, but to each his own.
Mel
'96 Safari, 250hp 3126 Cat, 132k miles