Asking for a friend, (really) He has a 36 foot HR with a Cummins. He's broke and this is his primary residence. Other than switching campgrounds seasonally and pumping tanks he has no miles on the oil but he feels he needs to change it before taking a trip. He's 75 and is in cancer treatment. $200 for an oil change is a lot of money. Can he put 10,000 more miles on this oil? thanks

Oil That sits, especially in a diesel, gets acidic even with the low miles. I say change it. But seeing as how he really has no choice I say run it. I’m sure it’s done all the time. When he gets the chance and money have it changed.

I would run it as is if I was healthy. In cancer treatment? Air up the tires and go.

And, I would find someone who would change it for a LOT less than $200 and DO IT!

Yeah - changing every year regardless of miles is the std. But let's get real - life ain't perfect and priorities change. His rig isn't going to suffer catastrophic damage by deferring an oil change.

Cummins 5 year old synthetic oil with 1000 miles - change ?

21 Replies

4x4ord
Explorer III
Nov 09, 2019
I have an old 1975 diesel tractor that gets oil changes every 5 years or so. Ive had it since new and with over 10,000 hours on it, it still runs like new.
hertfordnc
Explorer
Nov 08, 2019
rgatijnet1 wrote:
I would be more concerned about the tires sitting for so long than the oil. I would forget about the oil and drive a little slower than normal to get to the destination.

He did the tires in the last couple years and he drives slow enough :-)
rgatijnet1
Explorer III
Nov 08, 2019
I would be more concerned about the tires sitting for so long than the oil. I would forget about the oil and drive a little slower than normal to get to the destination. Of course you want to make sure that the tires are properly inflated with maybe some extra to keep them cooler. After the engine warms up it will burn off any moisture that has gotten in to the oil.
sundancer268
Explorer
Nov 08, 2019
My oil is going on 5 years and last year I only put on about 350 miles. Blackstone labs says to keep going as the oil is good and I am running Dino, not Syn. I would not worry about it especially for the short haul though I would put enough miles on it during the moves to get the engine and oil hot, maybe a 30-45 minute drive on the highway and not city streets.
twodownzero
Explorer
Nov 08, 2019
I sent my oil in for analysis after ~4 years and 14,227 miles and it was still perfectly fine and I could have left it in there.
Ivylog
Explorer III
Nov 08, 2019
Use the oil but I’d worry about the tires.
grldst
Explorer
Nov 08, 2019
I know very little about synthetic oil, just wondering does synthetic age or break down with age as much as real oil?
11178adm
Explorer
Nov 08, 2019
I would at least change the filter. if there was any moisture in the oil it could have caused the paper to deteriorate in 5 years. acid in the oil is'nt the problem that it was in the past due to ultra low sulfur diesel
Chum_lee
Explorer
Nov 08, 2019
Normally I'm not a fan of testing oil, (in lieu of changing it) but in this case, he could spend +-$40.00 and have the oil tested by a lab to see if it's fit for continued use.

Or there's the oil blotter test using a clean white business card for free.

https://www.machinerylubrication.com/Read/499/blotter-spot-method

Chum lee
ScottG
Nomad
Nov 08, 2019
I can't see how anyone can say it's OK to put 10K miles on that engines oil without knowing waht exact eng and year it is. A lot of Cummins engine didn't have anything near a 10K mile oil change interval.

As far as the acidic thing and old oil, I don't buy it. I once let an old car (1964 Thunderbird) sit for roughly 6 years and then I rebuilt the eng. The bearings didn't show any signs of being eaten by acid.
I can see the reasoning behind the theory but in pratice it doesnt seem to be an issue.