Oil Change interval for an off-road vehicle?

[Ang]

2010 Jeep Grand Cherokee 5.7
I know idling isn't great but this thing just idles around moving stuff occasionally. It basically never runs more than a few minutes at a time, so it's basically never even warm. Never goes above 10mph at best, the odometer will probably show 15 miles a year at best currently, so oil change is just time based. But how often?
It rattles on startup, 175k miles, but id like it to last as long as it can with its synthetic blend oil.

 

[Jetronic]

I'd go by fuel used. shouldn't be har to calculate how much fuel a normal used vehicle consumes per oci. when it has done that amount, change the oil.

 

[Lawnman23]

Every few years, whenever you remember to.

 

[Ang]

I'd go by fuel used. shouldn't be har to calculate how much fuel a normal used vehicle consumes per oci. when it has done that amount, change the oil.

Every few years, whenever you remember to.

So you are both just ignoring the fact that the oil will be full of water and gas quickly, and instead i should just match to an equivelent of a 4000 Mile oil change?

 

[Lawnman23]

So you are both just ignoring the fact that the oil will be full of water and gas quickly, and instead i should just match to an equivelent of a 4000 Mile oil change?

I was going off your description of this vehicle being nothing more than a barely used utility hauler akin to OPE. In which case, every few years.

If you are concerned with water/gas, then once a year to make it easy I guess.

 

[Ang]

I was going off your description of this vehicle being nothing more than a barely used utility hauler akin to OPE. In which case, every few years.

If you are concerned with water/gas, then once a year to make it easy I guess.

Yes it just drags stuff around. But it is a good vehicle that could be street legal if i put plates on it, so i would rather not neglect it. My main concern was about Water/Gas in the oil, So i was thinking the standard 4000 Miles/10-12 Months Was to long. But i guess 12-14 Months might be good.

 

[Lawnman23]

Yes it just drags stuff around. But it is a good vehicle that could be street legal if i put plates on it, so i would rather not neglect it. My main concern was about Water/Gas in the oil, So i was thinking the standard 4000 Miles/10-12 Months Was to long. But i guess 12-14 Months might be good.

Any particular reason to not get it registered? My 98 is in a similar boat, I just use it for truck stuff when needed but it doesn't get driven often. I keep it registered with just liability-only insurance rated for >5k a year mileage and it's dirt cheap that way.

This allows me to be able to take it out and about when I need to or feel like it and not have it only stuck at home.

 

[Ang]

Any particular reason to not get it registered? My 98 is in a similar boat, I just use it for truck stuff when needed but it doesn't get driven often. I keep it registered with just liability-only insurance rated for >5k a year mileage and it's dirt cheap that way.

This allows me to be able to take it out and about when I need to or feel like it and not have it only stuck at home.

Theres no reason to pay for registration, Along with Monthly Insurance on a vehicle thats not going on the road, Theres no reason to pay for registration plus $150 a month in insurance. It would still cost like $40 a month just to have plates with it still not being road legal. unless i need to start towing, then it doesn't really need to be on the road. i would love to be able to register everything i own without thousands a month in added cost But No insurance company will make one policy to cover any vehicle you want to drive.

 

[Hohn]

2010 Jeep Grand Cherokee 5.7
I know idling isn't great but this thing just idles around moving stuff occasionally. It basically never runs more than a few minutes at a time, so it's basically never even warm. Never goes above 10mph at best, the odometer will probably show 15 miles a year at best currently, so oil change is just time based. But how often?
It rattles on startup, 175k miles, but id like it to last as long as it can with its synthetic blend oil.

0w-40 and pray.

 

[Ang]

0w-40 and pray.

Why 0W-40? It doesn't get hot.

 

[Ang]

Why 0W-40? It doesn't get hot.

I see you just dump thick oil in all your vehicles for some reason.

 

[supton]

My ATV seems to need a change about once a year? but that has a wet clutch and shared transmission, so the oil needs are different. And I can tell when the oil is "old", not by color but by how hard it shifts. About the same as you, 10 to 20 miles per year, similar usage (except when pushing snow, then it gets run longer).

Not quite the same, of course. IMO I'd pull the dipstick a couple times of a year and inspect. When the level goes up, smells like gas, or otherwise seems off, change. Otherwise, just ignore it. Loads of people drive far long without bothering to check at all. Being EFI I am not sure that the cold start penalty is as bad as it is for carb equipment.

 

[Lawnman23]

Theres no reason to pay for registration, Along with Monthly Insurance on a vehicle thats not going on the road, Theres no reason to pay for registration plus $150 a month in insurance. It would still cost like $40 a month just to have plates with it still not being road legal. unless i need to start towing, then it doesn't really need to be on the road. i would love to be able to register everything i own without thousands a month in added cost But No insurance company will make one policy to cover any vehicle you want to drive.

Yikes, insurance and registration rates suck in your area unfortunately

I pay $240 a year for insurance and registration is $65 for the year, hence my earlier suggestion.

In your case, just run ST of whatever is on sale and change once a year if your truly worried about it.

 

[slacktide_bitog]

Try to take at least one long trip (10+ miles) a month. Change the oil at least every year.

 

[Jetronic]

So you are both just ignoring the fact that the oil will be full of water and gas quickly, and instead i should just match to an equivelent of a 4000 Mile oil change?

if it's full of gas and water, the oil level will rise. When that happens it should be obvious.

 

[HemiBenny]

Supertech 5w30 and a Supertech oil filter. Change it once a year if you’re concerned.
~$35 once a year for oil and filter shouldn’t break the bank and it will put your worried mind at ease.
If you can find some clearance oil and filters within that year, even better.

 

[Hohn]

Why 0W-40? It doesn't get hot.

Because this usage cycle loads the engine more at lower RPM. It's similar to slowing down the boat towing a water skier and the skier starts to plow through the water instead of riding on top of it.

In more precise terms, the shear rate relative to the loading is going down. Which meant a thicker oil is helpful to compensate to effectively pump up the shear rate.

In general, the higher the loaded RPM, the thinner the oil you can use. The lower the loaded RPM (or average RPM) the thicker the oil you need.

 

[CarlB]

2010 Jeep Grand Cherokee 5.7
I know idling isn't great but this thing just idles around moving stuff occasionally. It basically never runs more than a few minutes at a time, so it's basically never even warm. Never goes above 10mph at best, the odometer will probably show 15 miles a year at best currently, so oil change is just time based. But how often?
It rattles on startup, 175k miles, but id like it to last as long as it can with its synthetic blend oil.

Why not get a used oil analysis to determine the fuel dilution and rate that it's accumulating dirt/sand from off-road?

 

[Hohn]

I see you just dump thick oil in all your vehicles for some reason.

Because in my use case and in my vehicles, thicker is better.

If you have a vehicle that spends a long time unused, thicker is better because it leaves thicker films in place on the engine. This better resists corrosion.

Think of it this way: the only advantage of thinner oil is shorter time to build oil pressure and restore oil films. It just happens that in some cases this is an absolutely critical advantage. If you do lots of cold starts the northern USA where temperatures get bitter cold, the cold flow of a 0w-40 vs a 20w-50 might be 40% less wear or more. And if you do a lot of cold starts (say, daily winter commute, car parked outside), you need a viscosity the prioritizes cold flow in -10F or so temperatures.

But outside such a use case where thin oil's superior cold start delay makes a considerable difference, thicker oils will have lower wear. What are the use cases where thick oils have less wear?
1) Frequent hot restarts where the oil's already 100F or higher
2) low-rpm, low-shear usage
3) Prolonged inactivity where thicker residual film is helpful. (see #1, similar effect)
4) Steady state warm operation.

In other words, depending on how "cold" is cold to you and how you use your vehicle, a 0w-40 could be optimal. But a surprisingly high number of use cases actually favor some surprisingly heavy oils. I'm in Indiana and the optimal viscosity for my use case is no less than 40 grade hot and up to 15w cold, with up to 20w being OK if I'm garaged all winter and only have 4-5 truly cold (0F) starts per year.

A good rule of thumb is to look at the "w" check temperatures in SAE J300. 15w has a test temperature of -20C for cranking. If in your use case you almost never see such a temperature for a cold start, then 15w is sufficient cold flow for you. But that has to be in the context of how often you start the engine.


You want no more than 1% of your starts to be above 6000cP dynamic viscosity, and about no more than 10% of your starts to be above 3000cP viscosity. If your oil meets that general guide, it's not too thick. And it if far exceeds those lower bounds, you have room to go thicker with very little cold wear penalty and some hot wear and restart benefit.

 

[meep]

If you like the vehicle, interval probably means more than synthetic chemistry. I’d put in a name brand oil, from super tech on up, once every year or two. No need to be synthetic. Filter probably does not matter either. Maybe change in yearly and use the barely-used oil that comes out in the mower(s) which get good and hot and will boil the water out.

Or maybe twice a year let the jeep idle for 2 hours and get the oil up to temp?