Wish me oil luck!

[Fishtaco]

This weekend I am finally going to change the oil in my 06 to HPR 30 20W-60 high mileage mineral oil with added Zinc!
I am taking a chance but I would rather the chance than living with dry start leak down and the prospect of doing the lifters.
Lazy way may be? but after a year of discussing it we shall know the results one way or another through experience rather than rhetoric

 

[Irun]

Now it's your fault that I went back and read this thread. Sadly, the only thing I took away from it was, well, nothing concrete. Given your average temperature range, I can't see where running that oil will cause any harm. The 4.0L, like most inline 6 cylinders, is nothing more than a tractor engine, which wasn't exactly built to the same tolerances modern cars are.

https://wranglertjforum.com/threads/been-recommended-to-use-20w-60-oil-in-my-tj.50560/
Perth - Average temperatures (1991-2020)

Month	Min (°C)	Max (°C)	Mean (°C)	Min (°F)	Max (°F)	Mean (°F)
January	18	32	25	64	90	76.9
February	18	32	25.1	64	90	77.2
March	16	30	23.2	61	86	73.8
April	14	26	20	56	80	67.9
May	11	22	16.5	51	72	61.7
June	9	20	14.2	48	67	57.6
July	8	18	13.4	47	65	56
August	8	19	13.7	47	66	56.7
September	9	21	14.8	48	69	58.7
October	11	24	17.2	51	75	63
November	13	27	20.2	56	81	68.4
December	16	30	23	60	86	73.3
Year	12.5	25.1	18.8	54.5	77.3	66

 

[Fishtaco]

Now it's your fault that I went back and read this thread. Sadly, the only thing I took away from it was, well, nothing concrete. Given your average temperature range, I can't see where running that oil will cause any harm. The 4.0L, like most inline 6 cylinders, is nothing more than a tractor engine, which wasn't exactly built to the same tolerances modern cars are.

https://wranglertjforum.com/threads/been-recommended-to-use-20w-60-oil-in-my-tj.50560/
Perth - Average temperatures (1991-2020)

Month	Min (°C)	Max (°C)	Mean (°C)	Min (°F)	Max (°F)	Mean (°F)
January	18	32	25	64	90	76.9
February	18	32	25.1	64	90	77.2
March	16	30	23.2	61	86	73.8
April	14	26	20	56	80	67.9
May	11	22	16.5	51	72	61.7
June	9	20	14.2	48	67	57.6
July	8	18	13.4	47	65	56
August	8	19	13.7	47	66	56.7
September	9	21	14.8	48	69	58.7
October	11	24	17.2	51	75	63
November	13	27	20.2	56	81	68.4
December	16	30	23	60	86	73.3
Year	12.5	25.1	18.8	54.5	77.3	66

Its quite conflicting! Mechanics in Australia are running this oil in big block high mileage US engines that call for 10W-30 with great results but the high Zink may be a problem for the cats in my 06? I have been assured that the difference is actually miniscule to the users eye, Work Mechanics are actually laughing at me now after a year for using 10w-30 in a worn straight 6.

I am lucky enough to have a team of Mechanics that are more into older tech engines than the brand new they have to work on day to day

All I can do is try it

Remember I live in a world where 10w-30 Mineral oil is very hard to find unless bought at a huge premium on the net.

 

[Irun]

Its quite conflicting! Mechanics in Australia are running this oil in big block high mileage US engines that call for 10W-30 with great results but the high Zink may be a problem for the cats in my 06?

My bet is this would be the only draw back. The question is how long will it take for any zinc ash to accumulate in the converters?

I have a set of roller rockers I plan to install at some point. This will reduce the friction and make me think less about zinc, molybdenum disulfide, or other additives.