2UZ-FE Oil Cooler on 1UZ/3UZ-FE?

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EyesofThunder

Member
Messages
89
Location
Rockford, IL, USA
I have a 98 GS with a 1UZ-FE VVTi and I was thinking of adding the 2UZ Tundra oil cooler to do a couple things:

1. Warm cold oil. I am up north, so we have some pretty darn cold days here, and I start it up and head to 55-65 mph pretty quickly.
2. Ensure hot oil temps are controlled to coolant temps, so the oil will have somewhat less spikes in the summer on hot days when I get a bit spirited in driving

I use Amsoil ASM 0W20 and always do oil analysis, it shows good at 25k, but at the end oxidation is starting to creep up. So I know the oil is done. But if there is a possibility I can stave off oxidation/nitration some, by all means it is well worth doing.

I have had many cars with engine coolant engine oil coolers and really like the oil temp consistency.

I change my oil summer to summer (1 year, for me is right at 25k miles), was thinking if I did winter to winter, the oil is getting "old" in cooler ambient temps, so it might actually be longer oil life, or better oil analysis specs if I did.
 
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Zuffen

Super Moderator
Staff member
Messages
5,385
Location
Sydney, Australia
I don't understand why you would want to prolong the life of your oil until it is worn out?

Oil is a lot cheaper than an engine.

I replace my oil a lot sooner than I have to but then I have peace of mind that I'm doing the best I can for my engine whilst my right foot gives it a beating.
 

George_R

Active Member
Messages
920
Location
Russia, Moscow
Double that.
Based on a number of tests, I believe that by ~8000 km the set of additives in any oil becomes exhausted. So I tend to change oil more frequently

As for the oil cooler, it will do not help you warm the oil up any quicker than without one.
 

EyesofThunder

Member
Messages
89
Location
Rockford, IL, USA
I have been averaging 25000-30000 miles per oil change using Amsoil and doing oil analysis the oil is still in good shape at 25k, at 30k it is at a point where I change it, I shoot for 25k, but 30k is my outside limit. I'm at 268k miles now, runs awesome, Oil Analysis shows no abnormal wear metals or minerals. Everything is showing very very good. Especially for such a high mileage engine.

UOA proves it. When I did UOA on Castrol Syntec (black bottle) it tested very similar to the Amsoil at 25k miles when it was pulled at 10k. Big difference in the oils. The Amsoil at 25k shows a better TBN (Total Base Number) than the Castrol did at 10k.

But my reason for the oil cooler is 2 fold. 1. To prevent high temps, keeping the oil consistent with coolant temps which in general are stable. 2. To warm the oil in the cold winter months here. The faster it is warmed up the faster it boils off moisture and the faster it gets to the least amount of oil drag.

I don't subscribe to the school that one would try to get the coolest oil possible, but to keep the oil up to temp as fast as possible and to maintain the temp as stable as I can.

Oil coolers that run through the coolant WILL warm the oil much faster than no cooler. Cadillac ran them for many years, and may still for that reason. Gets the car getting best fuel economy as soon as possible. Coolant is up to running temp in 10 minutes even in very cold temps, that coolant is the same that is going through the oil cooler that the oil is going through. It doesn't bypass it, it gets warmed by it.
 
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melvinmelvin

Member
Messages
262
Location
Bangkok
Coming from a fairly cold climate myself I appreciate your oil heating approach, sounds good to me.

But 25k+ miles on the oil???????????????????
Thats a lot!
 

EyesofThunder

Member
Messages
89
Location
Rockford, IL, USA
Followup, still haven't installed cooler yet, lost the flow regulator bolt (that holds it on the engine), but at 318k miles now. Runs awesome, still running 25k+ oil changes. No one seems to agree that long drains work, but oil analysis has shown it is good on my engine in my conditions.

I have used between 2 and 3 quarts in the last 21k miles (can't remember) on Amsoil 5W30 signature series oil, has a small rear main seal leak that started on a recent trip to Florida and some high speed driving on I10 for a while. Its small, but a bit annoying.
 

EyesofThunder

Member
Messages
89
Location
Rockford, IL, USA
Long term, sadly my Lexus GS400 was back into by a semi. So she was retired at 328k miles. I never got to do the final oil analysis. I was over 27k on Amsoil Signature Series 5W30. The previous oil was Amsoil HDD, was in the car for 18 months and 27500 miles. Oil Analysis showed serviceable still, but I had already changed it. Probably would have been fully "done" at 30k. So 25k is changing with a comfortable margin.

I have a 2008 Lexus GS450h now with a 2GR v6. I miss my 1UZ V8 a lot, but the improved mpg is nice.

Looking for the bearing clearances on the 2GR now. Anyone have them?
 

gloverman

Well-Known Member
Messages
2,970
Location
Hamilton. New Zealand
Long term, sadly my Lexus GS400 was back into by a semi. So she was retired at 328k miles. I never got to do the final oil analysis. I was over 27k on Amsoil Signature Series 5W30. The previous oil was Amsoil HDD, was in the car for 18 months and 27500 miles. Oil Analysis showed serviceable still, but I had already changed it. Probably would have been fully "done" at 30k. So 25k is changing with a comfortable margin.

I have a 2008 Lexus GS450h now with a 2GR v6. I miss my 1UZ V8 a lot, but the improved mpg is nice.

Looking for the bearing clearances on the 2GR now. Anyone have them?
Due to the amount of oil in many industrial machines and trucks oil analysis is common place. Its can be a matter of saving money by prolonging service periods while still ensuring maximum engine life.
 
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