392 Swap - High Oil Temps - What Would You Do?

[1SLwLS1]

So I've got a 2013 crew cab with 3.92 rear gears, 8HP70 swap, and 392 swap with MMX NSR cam, stock bottom end, ported manifold, etc. This oil (Redline 5w-40) runs HOT and we're not even into summer (I am in TX).

Little background - fall of 2020 my 165K stock 5.7 decided to tire out and with the cost of new trucks and what I had recently put into the truck, I decided to keep it and upgrade the engine. Then I spent the following 2 years dealing with weak transmission issues and ended up swapping to an 8HP70. I finally got everything buttoned up and have been daily driving the truck since last summer/fall. At that time, when cruising 90 down the highway, I noticed the oil would routinely get well over 240-250F and raise the coolant temp up to around 220F - I have a 185F coolant thermostat that actually works but the delta between the engine's fluids could only be so high. Even putting around, the oil would always get over 220F and would probably average around 230F with reasonable highway speeds (60-70MPH), the coolant could somewhat manage this delta and would lower a bit, maybe around 200F.

So late last fall I put on an oil cooler (34 row 59K BTU) with 185F thermostat in the filter sandwich adapter. One of the problems with this setup was I had to use the small oil filter due to the 1.75" thick sandwich adapter. I thought the oil pressure was down ~5 PSI but I think it may be closer to a 10 PSI drop with the large cooler, I foolishly wasn't recording oil pressure and temperature on my logs until recently. Well that cooler got me through winter (great temps, pressure not so much) but I never liked the small filter and stumbled across a low profile sandwich adapter that allowed me to use the large filter (RP 20-820) and I put this on around mid-January. I did not realize that this low profile adapter did not have a thermostat of any kind and was full flow to the cooler all the time. So I took that off after two weeks and removed the cooler entirely and have been running nothing for about a month now but this oil is HOT and our ambient temps are only around 80F in the evening when I drive home. The coolant gets up 200F with the oil well over 240F cruising at 90 MPH for around 15-20 miles. The coolant falls back down to 185-190F when cruising at reasonable highways speeds and the EOT falls to around 220-230F.

So without the cooler, for oil pressure I would have low 60s at cold start idle, high 60s into the 70s at cold cruising, high 50s/low 60s warm/hot cruising, and plummet to high 30s at idle (800 rpm for cam). So I adjusted my tune (HPT) to raise idle depending on oil temp and basically it is unaffected until around 176F I bump it up to 825 (800 base), 875 rpm at 212F, and 975 rpm @ 240F all scaling between and it keeps me in the high 40s oil pressure at warm-hot idle. I would prefer higher idle oil pressures but c'mon 975 rpm idle on a street engine with tiny NSR cam seems about the limit of reasonable.

So with that said, what are other 392 truck owner's experiencing? I know this engine has the oil squirters to keep the pistons cool and I am sure they are working which is heating the oil considerably more than the 5.7 but also lowering idle oil pressure. Any other engine I would be okay with that pressure but these engines, particularly the lifters and camshaft, don't like to idle with low oil pressure. What would you do in my shoes?
1. Run 5w-50 oil - I already have to keep this handy for the Roush-charged mustang so it would allow me to consolidate engine oils.
2. Remote dual filters (30-8A)
3. Run the large oil cooler I have with a remote dual filter setup, would be rather expensive in parts setup
4. Run a smaller oil cooler
5. Run a smaller oil cooler with remote filter(s)
6. Hellcat oil pump - last ditch effort, I don't really want to tear into this
7. Moroso High Cap oil pan - also don't really want to headache with this
8. Some fancy A2W setup - big $$$
9. Nothing, f'in send it!
10. Some combination of choices or other??

 

[Burla]

I for sure would not change oil brands or formulas, I'd stay with that or that ilk, as in if not redline then hpl or something that is real synthetic. Your mineral oils are gonna break down in the summer, those wont. Redline is ester based, nothing handles heat like esters.

Ever think of larger oil pan? Something with more surface area?

Line 5 is redline oil along with line 2, so why go away from that? Base oils and operating temp ranges, the green part os the nature of the oil, or permanent performance aside from tbn loss.

 

[danielmid]

No personal 392 experience, but I think you're on the right path. I don't think it's going to be the cheapest option out of your list, but I would look at a remote filter mount with a thermostat built in that runs to the oil cooler you already have.

Improved Racing bypass to an Improved Racing remote filter mount with a thermostat built in. That way you can run the bigger 3/4-16 filters, oil cooler supported, and not over cooling the oil.

 

[Burla]

Some type pf skid plate that diverts air onto sump?

 

[1SLwLS1]

I for sure would not change oil brands or formulas, I'd stay with that or that ilk, as in if not redline then hpl or something that is real synthetic. Your mineral oils are gonna break down in the summer, those wont. Redline is ester based, nothing handles heat like esters.

Ever think of larger oil pan? Something with more surface area?

Line 5 is redline oil along with line 2, so why go away from that? Base oils and operating temp ranges, the green part os the nature of the oil, or permanent performance aside from tbn loss.


View attachment 515660

Definitely not changing oil brands, was just thinking about bumping up the weight from 5w-40 to 5w-50, for increased protection at the expense of some parasitic losses. I have option 7 as a high capacity Moroso pan, but that seems like a trial and error rabbit hole. They provide dimensions but no guarantees of fitment and a list of pickups, gaskets, dipsticks, etc. I think it could be done, just not sure if it is worth it.

I change my oil every 5000-5500 miles so if you're saying the oil can handle the heat, I would feel better, will definitely get another oil analysis at the end of this oil change, haven't had one since break-in and was focusing on transmission issues for a while, now this has my attention.

No personal 392 experience, but I think you're on the right path. I don't think it's going to be the cheapest option out of your list, but I would look at a remote filter mount with a thermostat built in that runs to the oil cooler you already have.

Improved Racing bypass to an Improved Racing remote filter mount with a thermostat built in. That way you can run the bigger 3/4-16 filters, oil cooler supported, and not over cooling the oil.

I priced a nice improved racing setup 2 years ago, to the tune of about $1000 for an oil cooler setup, and I was trying to shy away from this, but it may be the eventual direction.

I mean at the end of the day, I can either be at 220F with an oil cooler and lower pressure, or 240-250F without an oil cooler and slightly higher but similarly low oil pressure, without getting into the motor/pan.

 

[Wild one]

Definitely not changing oil brands, was just thinking about bumping up the weight from 5w-40 to 5w-50, for increased protection at the expense of some parasitic losses. I have option 7 as a high capacity Moroso pan, but that seems like a trial and error rabbit hole. They provide dimensions but no guarantees of fitment and a list of pickups, gaskets, dipsticks, etc. I think it could be done, just not sure if it is worth it.

I change my oil every 5000-5500 miles so if you're saying the oil can handle the heat, I would feel better, will definitely get another oil analysis at the end of this oil change, haven't had one since break-in and was focusing on transmission issues for a while, now this has my attention.


I priced a nice improved racing setup 2 years ago, to the tune of about $1000 for an oil cooler setup, and I was trying to shy away from this, but it may be the eventual direction.

I mean at the end of the day, I can either be at 220F with an oil cooler and lower pressure, or 240-250F without an oil cooler and slightly higher but similarly low oil pressure, without getting into the motor/pan.

One other option is to swap to 3.21 gears,as that'll bring your rpms down at 90 mph,lol. The 392's run hotter oil temps then most guys like that's for sure. There's a few guys with 3.90 geared 6 sp manual 392/6.4 Challengers that have commented on how hot their oil temps are after a 90 mph cruise of an hour or more.The 392 /steep gears and high speed cruising don't seem to go all that well together.My wifes 6.4 Challenger with 3.09 gears runs about 205 to 210 on oil temps on a hot day running at 90 mph with a 180 thermostat. If it was me,and i was hung up on keeping the 3.92 gears,i'd bite the bullet and install the hellcat oil pump,and plumb in the Improved Racings remote filter set-up with thermostat and external cooler.Or look into adapting the Hellcats engine oil cooler set-up to it

 

[crazykid1994]

Definitely look into a remote filter mount. A Thermostatic mount with a cooler is a nice option. Let’s you run the larger filter. Maybe a bigger cooling fan as well. The 5th gen hemi fan can fit our radiators. You can order a controller that will run it and just wire in triggers. Use the factory fan power to run 100% and wire a trigger with engine on to run low speed. That should help with engine cooling too. I’m not sure on the canbus system for your year truck but the controller I’m referring to can run off the trucks canbus system instead of trigger wires. I’m working with the guy to get it to work on my 2017.

 

[Wild one]

Definitely look into a remote filter mount. A Thermostatic mount with a cooler is a nice option. Let’s you run the larger filter. Maybe a bigger cooling fan as well. The 5th gen hemi fan can fit our radiators. You can order a controller that will run it and just wire in triggers. Use the factory fan power to run 100% and wire a trigger with engine on to run low speed. That should help with engine cooling too. I’m not sure on the canbus system for your year truck but the controller I’m referring to can run off the trucks canbus system instead of trigger wires. I’m working with the guy to get it to work on my 2017.

I've been watching your posts on facebook religiously Khris,lol. I think you'll get it figured out to where it'll be a plug-n-play operation to install the 5th Gens PWM electric fan set-up

 

[Bigskyroadglide]

My improved racing remote filter setup has definitely been a worthwhile investment.

I'm certainly not into mine for $1k. More like $350.

You certainly could look into this one. About $270 plus tax

HP10305 Remote Oil Filter for 2010-18 RAM 2500/3500 w/ 6.7L Cummins, Filter Thread of 1" - 16

Check out the deal on HP10305 Remote Oil Filter for 2010-18 RAM 2500/3500 w/ 6.7L Cummins, Filter Thread of 1" - 16 at Pacbrake

pacbrake.com

 

[Brandon-w]

When I did my swap my oil temps were average 240f. I never had any coolant issues but I set my e fan to come on early as I tow here n there and wanted to be on top of things.
I did a improved racing oil filter sandwitch block with 200f thermostat to my cooler and Havnt had high oil temps since.

 

[crazykid1994]

I've been watching your posts on facebook religiously Khris,lol. I think you'll get it figured out to where it'll be a plug-n-play operation to install the 5th Gens PWM electric fan set-up

Problem is I have no way of knowing if it’ll work on a 18 or newer 4th gen due to the security. It should because it’s only reading the canbus. And I’m not sure if 13-14 will be compatible. The 15-17 all use the same system. Plus I’m spending money to make it work and not making money so less incentive on my part.

 

[1SLwLS1]

One other option is to swap to 3.21 gears,as that'll bring your rpms down at 90 mph,lol. The 392's run hotter oil temps then most guys like that's for sure. There's a few guys with 3.90 geared 6 sp manual 392/6.4 Challengers that have commented on how hot their oil temps are after a 90 mph cruise of an hour or more.The 392 /steep gears and high speed cruising don't seem to go all that well together.My wifes 6.4 Challenger with 3.09 gears runs about 205 to 210 on oil temps on a hot day running at 90 mph with a 180 thermostat. If it was me,and i was hung up on keeping the 3.92 gears,i'd bite the bullet and install the hellcat oil pump,and plumb in the Improved Racings remote filter set-up with thermostat and external cooler.Or look into adapting the Hellcats engine oil cooler set-up to it

Definitely would change the oil pump before I bought a different rear end. Even driving 60-65 in 80F ambient, my oil temps climb to 230F but my coolant stays in check at around 185-190F.

Definitely look into a remote filter mount. A Thermostatic mount with a cooler is a nice option. Let’s you run the larger filter. Maybe a bigger cooling fan as well. The 5th gen hemi fan can fit our radiators. You can order a controller that will run it and just wire in triggers. Use the factory fan power to run 100% and wire a trigger with engine on to run low speed. That should help with engine cooling too. I’m not sure on the canbus system for your year truck but the controller I’m referring to can run off the trucks canbus system instead of trigger wires. I’m working with the guy to get it to work on my 2017.

I'm not sure airflow through the radiator at low speeds is the issue, I could certainly benefit from a larger radiator but when I slow down, the engine temperature starts to come down, I think I just have too much heat (a mo' powa baby!) in the system for the radiator. Either way, I would definitely be interested in the fan swap once you get all of the kinks worked out.

My improved racing remote filter setup has definitely been a worthwhile investment.

I'm certainly not into mine for $1k. More like $350.

You certainly could look into this one. About $270 plus tax

HP10305 Remote Oil Filter for 2010-18 RAM 2500/3500 w/ 6.7L Cummins, Filter Thread of 1" - 16

Check out the deal on HP10305 Remote Oil Filter for 2010-18 RAM 2500/3500 w/ 6.7L Cummins, Filter Thread of 1" - 16 at Pacbrake

pacbrake.com

The $1k was for a remote mount filter and oil cooler. It would be about $475 right now for the low profile take-off plate and a thermostatic remote filter mount, which is all I should need at this point since I already have the hoses and cooler.

When I did my swap my oil temps were average 240f. I never had any coolant issues but I set my e fan to come on early as I tow here n there and wanted to be on top of things.
I did a improved racing oil filter sandwitch block with 200f thermostat to my cooler and Havnt had high oil temps since.

At what temperature does your tune have the fans kick on? Tuner has mine come on early, maybe too early at 185F as they're always running at that set point. With the cooler and thermostatic sandwich plate, my temperatures are in check, but what is your hot idle oil pressure? With your sandwich plate are you running the small filter or the big filter?

 

[crazykid1994]

Not necessarily but it helps. I have my current setup so the fan runs low speed at all times unless otherwise needed to ramp up. You can always purchase the dongle and wiring to test the canbus and send a log to the guy and he can compare with mine to see if it’ll work. We already have the fan program working. I’m honestly just waiting on the other half of the dongle to show up to finish my end of testing. The v6 fan draws around 30 amps. The hemi fan is supposedly 600 watts which should be 50 amp draw plus the blades are a better design to draw more air through. There is a larger fan that is in the heavy tow package and I think the ecodiesel rated at 800 watts but I can’t say if it’ll fit our radiator. I’ve looked into a larger radiator but as of right now waiting for other people to have the full aluminum radiators for a bit longer before making the jump. Also this is how I setup my remote filter mount. I end up running higher temps due to off-roading. Low speed high rpms in 4wd for crawling around really heats things up

 

[1SLwLS1]

Not necessarily but it helps. I have my current setup so the fan runs low speed at all times unless otherwise needed to ramp up. You can always purchase the dongle and wiring to test the canbus and send a log to the guy and he can compare with mine to see if it’ll work. We already have the fan program working. I’m honestly just waiting on the other half of the dongle to show up to finish my end of testing. The v6 fan draws around 30 amps. The hemi fan is supposedly 600 watts which should be 50 amp draw plus the blades are a better design to draw more air through. There is a larger fan that is in the heavy tow package and I think the ecodiesel rated at 800 watts but I can’t say if it’ll fit our radiator. I’ve looked into a larger radiator but as of right now waiting for other people to have the full aluminum radiators for a bit longer before making the jump. Also this is how I setup my remote filter mount. I end up running higher temps due to off-roading. Low speed high rpms in 4wd for crawling around really heats things up

Yes I am definitely wanting more real world reviews and results on the larger aluminum radiators before committing, especially since this radiator is only 2 years old.

 

[Wild one]

My oil temps run right around 190/195 at 90 mph on a hot day with this set-up on my 2014 4X4,but it's also a 5.7,so if it'd work to bring your oil temps down to where you want on a 6.4 i'm not sure.One benefit was my oil pressures did come up with the dual filter set-up compared to the first single filter set up i ran.That's with 3.55 gears,8 speed and a 31" tall tire to

 

[Wild one]

I don't think anybody makes a deeper pan for the trucks,but you could do the old school set-up and modify your existing oil pan by deepening it.Either by cutting the bottom off another pan,and welding it your pan,which drops the bottom of the stock pan so it'll hold more oil,or by welding a strip of flat metal to your pan,i also have seen a couple old school home deepened pans,where guys had dropped the pan bottom by 3 or 4 inches,then welded tubes length wise into the deepened pan,to allow more airflow through the pan bottom.Just spit balling ideas at you

 

[1SLwLS1]

My oil temps run right around 190/195 at 90 mph on a hot day with this set-up on my 2014 4X4,but it's also a 5.7,so if it'd work to bring your oil temps down to where you want on a 6.4 i'm not sure.One benefit was my oil pressures did come up with the dual filter set-up compared to the first single filter set up i ran.That's with 3.55 gears,8 speed and a 31" tall tire to

Yea I saw your post on a thread from last summer and it intrigued me but I don't know if the complexity of adding that back with a cooler and a having to run an inline downstream thermostat is worth it over the simplicity of the single 3/4-16" remote filter with integrated thermostat. Do you get to increase your OCI's with the additional filtration or?

I don't think anybody makes a deeper pan for the trucks,but you could do the old school set-up and modify your existing oil pan by deepening it.Either by cutting the bottom off another pan,and welding it your pan,which drops the bottom of the stock pan so it'll hold more oil,or by welding a strip of flat metal to your pan,i also have seen a couple old school home deepened pans,where guys had dropped the pan bottom by 3 or 4 inches,then welded tubes length wise into the deepened pan,to allow more airflow through the pan bottom.Just spit balling ideas at you

I believe Moroso has one but it would be a lot more trial and error.

Does anyone know of a dual remote filter housing with thermostat built in? I cannot find anything but the internet is vast these days.

 

[HEMIMANN]

If high sump oil temp is the issue, I'd advise against going to higher viscosity. Viscosity is to minimize wear, but it reduces engine cooling both by lower heat absorption and slower flow rate.

The problem here isn't wear, it's temperature. Coolers are the right solution.

 

[Wild one]

Yea I saw your post on a thread from last summer and it intrigued me but I don't know if the complexity of adding that back with a cooler and a having to run an inline downstream thermostat is worth it over the simplicity of the single 3/4-16" remote filter with integrated thermostat. Do you get to increase your OCI's with the additional filtration or?



I believe Moroso has one but it would be a lot more trial and error.

Does anyone know of a dual remote filter housing with thermostat built in? I cannot find anything but the internet is vast these days.

I've only seen a Moroso pan for the front sump cars,but then again,i haven't actually went looking for an aftermarket pan for the trucks.If somebody does make a finned cast aluminium pan for the trucks,that would probably help your oil temps.
I'm not a fan of long oil change intervals,lol.
The transdapt set-up i'm running can be fed on both sides,so it'd be easy to plumb a thermostatically controlled oil cooler to it.
My oil temps did drop a bit when i went to the dual set-up,as the oil has 2 filters to radiate heat ,and it also came up a couple psi over the single filter set-up,plus it adds roughly another quart to the oil capacity..
I know you don't want to drop the pan and add the Hellcat pump,but i honestly think that's probably your best option,as you already have a couple oil cooler set-ups to play with,and in the long run,it might be cheapest option,as it'd allow you to keep the oil pressures up at idle,and provide more then enough volumn to utilize one of the coolers you already have on hand

 

[danielmid]

Yea I saw your post on a thread from last summer and it intrigued me but I don't know if the complexity of adding that back with a cooler and a having to run an inline downstream thermostat is worth it over the simplicity of the single 3/4-16" remote filter with integrated thermostat. Do you get to increase your OCI's with the additional filtration or?



I believe Moroso has one but it would be a lot more trial and error.

Does anyone know of a dual remote filter housing with thermostat built in? I cannot find anything but the internet is vast these days.

I suppose you could to engine adapter -> dual filter mount -> in line thermostat -> cooler? I think the dual input/outputs on the filter mount would accommodate this and the in line thermostat would flow back, but I don't know this for 100%.

That seems like a lot of fittings to add a second filter.