Looking for a better engine oil

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Originally Posted by Graeme

I recently switched from Castrol Magnatec 5W30 to Castrol Edge A3/B4 5W40 for increased bearing protection including for when towing in hot weather for the 4.4 TDV8 in my L322. A digital oil pressure gauge is fitted.
Idle oil pressure from as soon as the oil is up to temperature has consistantly been 12-13 psi which is as per specs for normal operation. However a climb up to the top of the Warrumbungles from the west using gears manually while towing a 2T van caused idle oil pressure to only be 9 psi when stopping at the van parking area for the observatory. Whilst this is still above minimum specs, it seems to indicate that the oil doesn't maintain its viscosity at higher temperatures.

Is there another A3/B4 5W40 oil that has better stay-in-grade characteristics?

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Hi Graeme,
Do you know what oil temp you have in the above scenario?

According to the Castrol spec sheet it has a kinematic viscosity of 13.4 at 100deg C

Penrite HPR 5 5W-40 Full Synthetic is 14.4.

I really have no idea if this is a significant difference or not, or what difference it would make to your hot oil pressure.

I guess you could go through all the 5W40 oil specs and pick the one with the highest hot viscosity.

Hopefully Rick will chime in.

Tony

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Originally Posted by Graeme

Maybe next time I'll try Penrite HPR 5 5W40 (full synthetic) to see if it stays in grade any better. It meets the Ford specs and has my preferred A3/B4 rating rather than the fuel efficient A5/B5 rating.

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I've been running HPR5 for 36,000 klms now (total, 206,000) and seeing excellent results on my oil analysis.
Very pleased with it.
Absolutely no oil used between 7-8,000 klm changes.
I also use the Wynns "Professional" oil additive. (black bottle, only available for the "Trade").

I didn't think to check the coolant and oil temps at the time. The oil temp gets to 95-98 degC quite quickly just on the 15 km drive the PO and back, after which idle oil pressure is 12-13 psi so the viscosity at around 100 deg is OK.

When stopped after the climb to unhitch the caravan for the drive up to the observatory where no vans or trailers are allowed, the engine smelt quite hot which surprised me because I considered that I had been driving quite gently. However I've since deduced that as only the primary turbo would have been in use (1500-2000 rpm, light throttle) that some minor oil contamination on the exhaust cross-over pipe from a previous leak was most likely what I smelt, not the engine generally although the engine must have been somewhat warm for the oil to thin, possibly around 115 deg from my esperience with an overheating TD5 engine. I don't recall hearing the cooling fan roaring which it does on hot days, but perhaps it was and I ignored it due to other concerns. The coolant reservoir level is still at its usual spot.

As I understand, engine oils are supposed to stay within grade up to 150 degC, well above the point at which aluminium heads go soft. I'm aware of the various 100 degC kinematic viscosities, including the 9.6 of the LR recommended Castrol oil, but my concern is that my current Castrol oil appears to not be staying in grade at not much above 100 deg. I prefer not to go to a higher viscosity oil, not wanting to reduce flow during warm-up, but may try the Penrite oil regardless, hoping that it stays in grade at the slightly elevated temperature. After all, this was mid-winter at an elevated altitude, not a 40 deg summer's day.

Quote:

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Originally Posted by Graeme

I didn't think to check the coolant and oil temps at the time. The oil temp gets to 95-98 degC quite quickly just on the 15 km drive the PO and back, after which idle oil pressure is 12-13 psi so the viscosity at around 100 deg is OK.

When stopped after the climb to unhitch the caravan for the drive up to the observatory where no vans or trailers are allowed, the engine smelt quite hot which surprised me because I considered that I had been driving quite gently. However I've since deduced that as only the primary turbo would have been in use (1500-2000 rpm, light throttle) that some minor oil contamination on the exhaust cross-over pipe from a previous leak was most likely what I smelt, not the engine generally although the engine must have been somewhat warm for the oil to thin, possibly around 115 deg from my esperience with an overheating TD5 engine. I don't recall hearing the cooling fan roaring which it does on hot days, but perhaps it was and I ignored it due to other concerns. The coolant reservoir level is still at its usual spot.

As I understand, engine oils are supposed to stay within grade up to 150 degC, well above the point at which aluminium heads go soft. I'm aware of the various 100 degC kinematic viscosities, including the 9.6 of the LR recommended Castrol oil, but my concern is that my current Castrol oil appears to not be staying in grade at not much above 100 deg. I prefer not to go to a higher viscosity oil, not wanting to reduce flow during warm-up, but may try the Penrite oil regardless, hoping that it stays in grade at the slightly elevated temperature. After all, this was mid-winter at an elevated altitude, not a 40 deg summer's day.

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Since your Castrol and my HPR5 are both "5W" they should have very similar characteristics when cold.

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Originally Posted by Discodicky

Since your Castrol and my HPR5 are both "5W" they should have very similar characteristics when cold.

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The oil Graeme is using has a 40deg C viscosity of 80.5.
Penrite HPR Diesel 5 is 89.0

So it would appear to have a bigger difference when cold than hot.

I will say again, I don't really understand what difference these numbers would make in the real world.

Tony

The Penrite makes a bigger difference at -30C, the 5W part of the spec, although I'm considering Penrite HPR 5 5W40 (full synthetic) rather than Penrite HPR 5W40 (semi-synthetic). However I'm concered as to low the viscosity gets at 110/115C.

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Originally Posted by V8Ian

If using diesel oil in a petrol motor, only do so from new. I used diesel oil in a high mileage, petrol Cruiser motor, years ago. End of engine, the diesel oil had more detergent than the petrol oil. Not sure if that situation is still relivant.

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I'm now using a terrifyingly light Winter, Diesel, Full - Synthetic oil in the v6 Camry after a savage engine-flush which went for days - and seems to have done the job. Secret seems to be 'Flush first, then use diesel oil for more detergency'.
- Camry V6 (3 litre 1MZ-FE) are known for sludging up, more so when driven by Little Old Ladies, like mine, for 200K.

After 600km engine dipstick is golden 'clear', and not leaking/burning anything noticeably. This also appears to have sorted what I thought was valve-stem seals, ie, sometimes start-up was greeted by laying a smokescreen for 3 to 5 minutes..[bigsad]
In the US, Toyota now suggest '0W-8' in temperate areas.

https://www.youtube.com/watch?v=sALAUhldASc


- And I used to think 15W-30. was courting catastrophe !

My few cents of experience.

Oils with higher detergents only cause trouble on engines which had trouble to begin with in general. The detergents flush away dirt that prevented leaking and... your engine starts leaking. If you would not dare to flush your engine then using an oil with higher levels of detergent might worry you as well. Then again, perhaps it was about time to replace the seals etc anyway.

In the past going from normal to synthetic oils caused trouble to seals since they responded differently. Not sure if that is still the case in modern-ish engines and seals.

Oils with higher zinc levels aka ZDDP (I am not sure if diesel oil does contain more ZDDP) are very useful for flat tappet engines since the zinc leaves a sacrificial layer on the cam etc. to deal with the few seconds after starting when there is no or insufficient oil to lubricate. Flat tappet engines are mostly a thing of the past though :)

This guy 540 RAT - Tech Facts, NOT Myths seems to strongly argue that it does not matter anymore, just have an oil with high pressure protection and he made a very large table with all sorts of oil. I do not know anything about his credibility but I have run a high scoring oil for high mileage engines from his list for 6 years in 7 different cars (bought a full drum of it to share amongst family and mates) and I had no problems with it whatsoever (valvoline 5w30 long life c3).

The former guy also suggest indeed that you should use the thinnest oil with the best high pressure protection that gives you sufficient oil pressure.

Cheers,
-P

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Originally Posted by Pedro_The_Swift

You dont think LR would use a less than stellar oil just to increase its fuel numbers Graeme?.... omg shock horror..

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real world figures with my tdv6 in a territory.

penrite hpr5 5w-40 best mileage achieved on a tank of juice 980klms

castrol magnatec start stop 5w-30 (but specs place it closer to 20 than 30) i achieved 1020klms

done that same test twice now and results were almost identical

make of it what you will.....

i normally run penrite 5w-40

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Originally Posted by prelude

My few cents of experience.

Oils with higher detergents only cause trouble on engines which had trouble to begin with in general. The detergents flush away dirt that prevented leaking and... your engine starts leaking. If you would not dare to flush your engine then using an oil with higher levels of detergent might worry you as well. Then again, perhaps it was about time to replace the seals etc anyway.

In the past going from normal to synthetic oils caused trouble to seals since they responded differently. Not sure if that is still the case in modern-ish engines and seals.

Oils with higher zinc levels aka ZDDP (I am not sure if diesel oil does contain more ZDDP) are very useful for flat tappet engines since the zinc leaves a sacrificial layer on the cam etc. to deal with the few seconds after starting when there is no or insufficient oil to lubricate. Flat tappet engines are mostly a thing of the past though [emoji4]

This guy 540 RAT - Tech Facts, NOT Myths seems to strongly argue that it does not matter anymore, just have an oil with high pressure protection and he made a very large table with all sorts of oil. I do not know anything about his credibility but I have run a high scoring oil for high mileage engines from his list for 6 years in 7 different cars (bought a full drum of it to share amongst family and mates) and I had no problems with it whatsoever (valvoline 5w30 long life c3).

The former guy also suggest indeed that you should use the thinnest oil with the best high pressure protection that gives you sufficient oil pressure.

Cheers,
-P

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This video from a specialist rebuilder of Rover V8s reinforces everything you said.

https://youtu.be/34fHcwuqB04'si=6AtEGsnYroedPExi

That variety of ZDDP rich Valvoline seems not to be available in Australia

I’ve read similar oil recommendations for old school BMW petrol engines from the E30 era. These also use a 20W50 oil spec.