Would changing to an oversized filter on the 3MZ-FE engine (in my Sienna & Highlander) have an effect on oil temperatures--would it make it a bit cooler, or a bit hotter? I have read something about this, but only in scattered comments here, and I figured I'd ask a question rather than state what I had read, and then have people later on read only my OP and then pass it on as truth. So would oversizing have any effect on oil temps?
Effect of oversized filters on oil temperature
- Thread starter paulri
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No effect, you are adding way less than a half qt to the capacity. It can't hurt filtration wise, but as an oil cooler you wopon't notice the difference
The larger surface area of the filter technically exposes the hot oil to more cooling (filter) surface than with the OE filter but I've never seen any data and I doubt you would actually see a difference on an oil temp gauge.
The oil doesn't stay in the filter long enough to have an affect.
Seeing as how I can cook a pot of rice and it's still hot after sitting on the counter for an hour, I doubt the small surface area and heat transfer rates would make any difference to oil temps. The filter would need to have a liquid cooled jacket around it to carry any meaningful amount of heat out of the thing. And, yes, rice is used in all official testing protocols for thermal transfer rates of motor oils. 
I have a new car that runs the oil a little too hot for my liking. It's new and it's considered normal but to me it's a wee bit too hot. This car has a digital oil temp gauge and it routinely runs 225-230F driving easy and will quickly go up to the 240's if you play with the go pedal. So far it's been as high as 249F driving up a mountain road and I wasn't even hot-dogging it since it was under the full-use break-in mileage recommendation.
The manufacturer 'recommends', yet requires an oil change every 6 months under warranty or 6 K miles whichever comes first. ( If you want the engine warranty to remain in effect.) I'm at 1,203 miles and I will be changing it with the manufactures recommended Pennzoil Ultra Premium 0W40 and a high perf "SRT" OE filter.
The car already comes with a factory oil/water intercooler and it still runs this hot. (The coolant temps stays between 215 and 227 most of the time.) Again, supposedly normal. So, when I change the filter I'm going to add this doodad to the outside of the oil filter since I've had it laying around the garage for about the last 30 years and now I finally have use of an oil filter that it will fit on. It may not do anything but I'm guessing it can't hurt.
The manufacturer 'recommends', yet requires an oil change every 6 months under warranty or 6 K miles whichever comes first. ( If you want the engine warranty to remain in effect.) I'm at 1,203 miles and I will be changing it with the manufactures recommended Pennzoil Ultra Premium 0W40 and a high perf "SRT" OE filter.
The car already comes with a factory oil/water intercooler and it still runs this hot. (The coolant temps stays between 215 and 227 most of the time.) Again, supposedly normal. So, when I change the filter I'm going to add this doodad to the outside of the oil filter since I've had it laying around the garage for about the last 30 years and now I finally have use of an oil filter that it will fit on. It may not do anything but I'm guessing it can't hurt.
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Great choice on the oil. Always run syns when you have any concerns about oil temps. BTW, you could easily change the syn oil out at 5K intervals and the filter every other time, at 10K intervals.
4WD
$50 site donor 2024
Yeah, had that finned cooler on a remote transmission filter … what the heck, $20
The motor might be a bit tight if it's still breaking in. Maybe the oil temp will be a little less after full break-in.
As the oil is 'cooled' by the engine coolant, you would benefit from a lower temperature thermostat.
BUT that is near impossible to find these days.
Modern thermostats are 205°. Would be great if we could find a 180° one, but don't hold your breath.
My 2¢
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If there is airflow around filter, the filter shell surface area acts like a cooler
There is more 'dwell' time for the oil to cool in the pan
The only question is..... how much sump capacity and filtration size does it take to be to be measurable?
I guess at least 1 automaker swapped form a small filter to a PH8A sized filter to make up for the poor enginesneering known to sludge 1.8T with overly small sump.
A couple square inches and a couple ounces isn't enough. So, if you want more oil capacity, then use the bigger filter. The benefit is there even you don't see it. And, I bet it would fit all 3 cars in your signature.
There is more 'dwell' time for the oil to cool in the pan
The only question is..... how much sump capacity and filtration size does it take to be to be measurable?
I guess at least 1 automaker swapped form a small filter to a PH8A sized filter to make up for the poor enginesneering known to sludge 1.8T with overly small sump.
A couple square inches and a couple ounces isn't enough. So, if you want more oil capacity, then use the bigger filter. The benefit is there even you don't see it. And, I bet it would fit all 3 cars in your signature.
Need to electronically adjust fans as well then, probably wouldn't be great for warranty, but yep that's how you do it.
I think your oil temperatures are perfectly fine.
I wonder if a device like that would not work as well or even increase the temps of the filter if there isn't some sort of thermal paste applied between the two metal surfaces?
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On 0w20, my 1.4T runs 180-190F all day, in Florida heat. I can hit 210F when speeding on the highway. I am content with the temps and the oil grade. But, I do spike the viscosity a little and haven't noticed an oil temp difference.... even ran Dexos and a 504 oil once too. So, if an overly stressed small engine pushing 3500 lbs only chills around 200F, how happy are you with 215-227?
I don't run oversized oil filter for any ONE reason. I run them for ALL possible reasons:
oil temp
oil capability
filtration capacity
filtration flow
cooling
late OCI
automaker misengineering(primary reason)
No thermal paste is needed. The filter collars work great. And again, you might not see the gauge temp difference but you will burn yourself when you touch them.
Engine coolant is just one part of the oil cooling. It has limitations. And, it will also heat the oil if the oil is cold and coolant is warmer. Better than nothing but oe heat exchangers are nothing to get excited about....
I don't run oversized oil filter for any ONE reason. I run them for ALL possible reasons:
oil temp
oil capability
filtration capacity
filtration flow
cooling
late OCI
automaker misengineering(primary reason)
No thermal paste is needed. The filter collars work great. And again, you might not see the gauge temp difference but you will burn yourself when you touch them.
Engine coolant is just one part of the oil cooling. It has limitations. And, it will also heat the oil if the oil is cold and coolant is warmer. Better than nothing but oe heat exchangers are nothing to get excited about....
Yep, the dealer says oil & coolant temps are normal, that's why FCA specs the 0W40 PUP at 6 mo/6k intervals. It was so easy to hit 249, I imagine I'll get into the high 250's easily when I start really playing with the fun pedal.
A cooler thermostat would necessitate a non-OE (aftermarket) ECM reprogramming which would void the engine warranty. FCA began locking the ECM's on the 2018 & up model years to prevent aftermarket tunes from being installed. To get around it you have you obtain another ECM ($), have it unlocked ($), and re-programmed ($) and swap it out (PITA).
Never thought about the thermal paste. I'll keep and eye on it and see if it makes any difference. It's easy to take off so if I see a problem, it's easily gone.
Thanks for the comments.
A cooler thermostat would necessitate a non-OE (aftermarket) ECM reprogramming which would void the engine warranty. FCA began locking the ECM's on the 2018 & up model years to prevent aftermarket tunes from being installed. To get around it you have you obtain another ECM ($), have it unlocked ($), and re-programmed ($) and swap it out (PITA).
Never thought about the thermal paste. I'll keep and eye on it and see if it makes any difference. It's easy to take off so if I see a problem, it's easily gone.
Thanks for the comments.
250F is still within the normal range of oil temps. Definitely at the higher end but still within normal. As long as it doesn't go above that, I would not worry. Synthetic oils can withstand repeated blasts to 275F and still work perfectly fine.
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Or if the filter is close to an exhaust pipe or exhaust manifold, the fins might actually absorb heat and make the oil hotter in some conditions. I have seen a few vehicles with the filter way too close to the exhaust.
Yeah my 1995 LT1 Corvette has the oil filter right next to a catalytic converter. Good thing they put a heat shield around the cat.
