Valvoline Maxlife Synthetic and High Oil PSI

[e55amgbenz007]

I recently changed the oil in a new to me 2000 3.4 V6 4Runner with Maxlife Synthetic and have noticed that the initial oil pressure is at 75PSI. When the car is warm, the oil is at about 20-25PSI. The previous owner stated that the last OCI was M1 5W30 and I did notice, when driving the car back from Texas to San Jose, that the pressure of this oil never even came close to 75 PSI. Is the oil pressure at 75 PSI too high? It has me a bit worried. I would rather keep the Maxlife in, but if the PSI is too high, I am going to dump it for some M1 EP in the stash. Any thoughts?

Thanks

 

[147_Grain]

Perfectly normally.

Maxlife is a thick oil that raised your oil pressure as designed.

 

[Zaedock]

Originally Posted By: 147_Grain
Perfectly normally.

Maxlife is a thick oil that raised your oil pressure as designed.



Maxlife Syn and Mobil 1 5W30 have nearly identical advertised viscosities.

 

[dustyroads]

Fresh oil that hasn't yet sheared or been diluted will provide higher psi for awhile...at least cold. As long as it comes back down once it's at normal temp it's probably normal. Although 75 seems kind of high...it must be short lived.

I would expect the cool oil psi to moderate after some miles. I base all this from many years watching oil psi on my trucks.

Maybe there's a better explanation but I feel confident that is probably it...if u change it out I bet you'll see more of the same.

 

[dustyroads]

Fwiw I once had a diesel that had a defective oil pressure regulator that allowed too much psi all the time and had high oil usage until it was fixed...

 

[e55amgbenz007]

The cold PSI of the Maxlife is approximately double that of the M1. If their properties are within the same range, why would one oil double up on the PSI? Any thoughts/discussion would be appreciated.

 

[dustyroads]

I still say it's due to new oil. If the m1 had a bunch of miles on it then it's properties had most likely changed and not like the fresh maxlife. Specifically lower viscosity. They may have similar vis as new oils, but new and used can be much different.

Your maxlife is fine at operating temp, right?

Fresh maxlife with good vis, old m1 with lowered vis. The maxlife may show lower psi once it has bunch of miles on it. I think your good....

 

[OVERKILL]

Originally Posted By: e55amgbenz007
The cold PSI of the Maxlife is approximately double that of the M1. If their properties are within the same range, why would one oil double up on the PSI? Any thoughts/discussion would be appreciated.


What grade of Maxlife did you use, 5w-30? (you didn't say in your OP).

 

[e55amgbenz007]

Thank you guys for taking the time to respond. I used the 5W30 Maxlife Synthetic.

 

[e55amgbenz007]

What would you guys say that the optimal/normal PSI should be?

 

[GenSan]

How is your oil psi at idle? Your 5vz-fe should be around 4psi at idle once normal operating temps have been reached. Here are oil psi specs: link .

 

[crazyoildude]

hm oils are generally blended on the higher side of the viscosity chart im not sure about those two although they are good oils..

 

[CATERHAM]

High mileage oils are heavier, but Valvoline doesn't provide the HTHSV of their oils which oil pressure tends to correlate to for us to compare with M1 5W-30 directly.
It does have a slightly lower VI at 168 than M1 5W-30 so yes it does sound like it is a heavier oil.

I think your oil pump by-pass point is set at around 75 psi but as long as you're no longer in by-pass when the oil is up to temperature at high rev's over 3,000 rpm, the oil your running now isn't too heavy to justify dumping it.

At the next oil change I'd try a lighter 30wt oil such as Pennzoil Platnium 5W-30.

 

[CATERHAM]

I should also point out that your 4Runner is back spec'd to include the 5W-20 grade as an option at least in Canada. See below:

https://bobistheoilguy.com/forums/posts/2638784/

So on second thought I'd suggest running a cheap 5W-20 or even M1 0W-20 which is heavier 20wt oil.

 

[Zaedock]

I've had plenty of experience rebuilding engines, some with HV oil pumps. It wouldn't matter if you used 10W40. No oil is going to double your cold oil pressure.

The oil gauge may have an issue, the filter may have an issue(if the bypass is in the filter), or perhaps the owner didn't use Mobil 1 5W30. Scan through Craigslist and see how many vehicles run "Mobil"e" 1 changed every 3,000 miles".

Either way, there is no need to change out the Maxlife.

 

[uart]

Since the viscosity @40C of most oils is at least 5 to 6 times that at 100C, then I would expect most oils to be able to peg a 75psi bipass when cold (under 40C).

 

[e55amgbenz007]

One thing that I completely forgot to mention....I did use an oversize filter (M1-209) with the Maxlife. Could this contribute to the PSI jump?

 

[uart]

Originally Posted By: e55amgbenz007
One thing that I completely forgot to mention....I did use an oversize filter (M1-209) with the Maxlife. Could this contribute to the PSI jump?


Can you fill in some more details.

1. What cold oil pressure were you getting with the previous fill?

2. How does the hot oil pressure compare with new oil versus the old?

3. What RPM are measuring it at? (roughly)

 

[e55amgbenz007]

Previous cold PSI w/ M1 was approximately 40.

The hot oil pressure of the Maxlife seems comparable to the M1.

The cold PSI was observed while driving approximately 15 mph @ 1200-1500 rpm I do believe.

 

[rrounds]

Oil pressure At idle speed (normal operating temperature)4.3 psi) or more
At 3,000 rpm (normal operating temperature)36 - 75 psi)

That is a he## of a spread on the high side with hot oil 36 to 75 psi and you need only 4.3 psi at idle, that tells you you don't need too much oil pressure at low rpm's like when you're at a stoplight.