The 6.4 HD Hemi Thread

[AlexC2350]

Napa is having a sale on pup right now, 6$ and some change so I bought 3 oil changes worth. I hope she’s likes it haha


Sent from my iPhone using Tapatalk

 

[dl2011ms3]

So, I have a 2018 and was wondering what you guys normally see as far as coolant and trans temp when just around town unloaded. I regularly see 210* coolant temp. Ambient here in Texas has been above 90* each time I've bothered to look at it.

Sent from my Pixel 4 XL using Tapatalk

 

[RandomRam]

So, I have a 2018 and was wondering what you guys normally see as far as coolant and trans temp when just around town unloaded. I regularly see 210* coolant temp. Ambient here in Texas has been above 90* each time I've bothered to look at it.

Sent from my Pixel 4 XL using Tapatalk

Once up to operating temp I see the following: Coolant 215-220, Engine oil 220-225, and transmission 170. Keep in mind I have the ZF 8HP in my 2019.

 

[Bldrinker]

So, I have a 2018 and was wondering what you guys normally see as far as coolant and trans temp when just around town unloaded. I regularly see 210* coolant temp. Ambient here in Texas has been above 90* each time I've bothered to look at it.

Sent from my Pixel 4 XL using Tapatalk

I have a 2018.
Unloaded 212 water
Loaded I have seen 228 and I was super nervous, fan was screaming and I kept backing out of throttle to about 1/4throttle.
This was on a large climb with 12,000lbs during summer.

 

[dl2011ms3]

I have a 2018.
Unloaded 212 water
Loaded I have seen 228 and I was super nervous, fan was screaming and I kept backing out of throttle to about 1/4throttle.
This was on a large climb with 12,000lbs during summer.

That's the info I was looking for. Truck hasn't hit 11k yet and I bought it used at 9700. Wasn't sure what normal was. I appreciate the input fellas.


Sent from my Pixel 4 XL using Tapatalk

 

[dl2011ms3]

Found this replacement that should be able to bring down temps. I wonder if it'd be worth it.

Sent from my Pixel 4 XL using Tapatalk

 

[AFMoulton]

Change your thermostat first before you pay fro a radiator.

Pulling my 38’ sail that weighs 10k behind my truck I see 210-225 on coolant temps, that’s through the Rockies. I use really good oil so the 225-240 while towing doesn’t bother me.

One thing you need to do is remove the thermostat block in the transmission coolant lines. After I did that, even on 95* days here in NM pulling up a mountain, my trans temp has never seen over 163*.

https://www.atsdiesel.com/ats2/productdetail.asp?p=3100052392&D=1




2018 Ram 2500 6.4L 4x4
Amsoil SS 0W-40

 

[dl2011ms3]

Change your thermostat first before you pay fro a radiator.

Pulling my 38’ sail that weighs 10k behind my truck I see 210-225 on coolant temps, that’s through the Rockies. I use really good oil so the 225-240 while towing doesn’t bother me.

One thing you need to do is remove the thermostat block in the transmission coolant lines. After I did that, even on 95* days here in NM pulling up a mountain, my trans temp has never seen over 163*.

https://www.atsdiesel.com/ats2/productdetail.asp?p=3100052392&D=1




2018 Ram 2500 6.4L 4x4
Amsoil SS 0W-40

Good info man! I don't see a thermostat bad at 11k miles but weirder things have happened. Definitely gonna look at the trans block bypass. Appreciate it.

Sent from my Pixel 4 XL using Tapatalk

 

[AFMoulton]

Good info man! I don't see a thermostat bad at 11k miles but weirder things have happened. Definitely gonna look at the trans block bypass. Appreciate it.

Sent from my Pixel 4 XL using Tapatalk

Mine runs 210+ on 96* days right now in NM. I don’t mind it so much. Truck runs good, but getting the trans temp down was the important thing for me.


2018 Ram 2500 6.4L 4x4
Amsoil SS 0W-40

 

[Bldrinker]

So what is to hi on the coolant temps?

 

[Joizee camper]

AFMoulton - I didn't know this thermostat block was inline between the trans and the cooler. Seriously thinking I should get this product. Thanks for adding the video!
Bldrinker - If I saw coolant temps at 230*, I'd slow down and assess whats happening. Am I pushing too hard? Am I low on coolant? In my book this is the time to get a bit concerned and follow up accordingly. Pull over and check sh*t out.

 

[AFMoulton]

Temps today while pulling 12000#s


2018 Ram 2500 6.4L 4x4
Amsoil SS 0W-40

 

[Joizee camper]

Can't beat those numbers! looking good!

 

[NewBlackDak]

AFMoulton - I didn't know this thermostat block was inline between the trans and the cooler. Seriously thinking I should get this product. Thanks for adding the video!
Bldrinker - If I saw coolant temps at 230*, I'd slow down and assess whats happening. Am I pushing too hard? Am I low on coolant? In my book this is the time to get a bit concerned and follow up accordingly. Pull over and check sh*t out.

Agreed. I’ve never seen coolant temps above 220°. I have seen oil temps get that high, but not coolant. That includes dragging 13K lbs up a 6% grade for miles on a 90° day.


Sent from my iPhone using Tapatalk

 

[Joizee camper]

I found this chart on https://durathermfluids.com/pdf/techpapers/pressure-boiling-point.pdf
I'm not associated with this paper or those that wrote it but this rings true from what I remember in High School auto shop 100 years ago! lol I don't have the 6.4L truck with me I have the 2017 2500 with the 5.7L and it has a 16PSI cap. IF the coolant is perfect mix of 50/50 you wont boil over until 267*F. I imagine there would be lots of indications of trouble WAY before you ever got to this high of a coolant temp! Knocking, loss of power, check engine, etc..

 

[Joizee camper]

Just to update: After replacing the thermostat block with the ATS bypass unit, trans temps now range from 135 - 148 degrees F. Temps were about 172 - 178 before. I have a small leak at the bypass block but that was my fault, I pinched an o-ring during installation. Very impressed with that temp drop!! Hemifever sent me the final 93 tune for the truck. I don't like the vibration caused by the MDS so I had that shut off. I haven't had the tune in long enough to see a fuel mileage difference. The biggest increase in power is right off idle. More low RPM grunt in the seat dyno.

 

[Tunaman]

I just want to add something about why a 2500 when I am only towing 5500lbs. I looked really hard at the 1500. Yes, it can tow 5500 lbs. The issue with the 1500 is that it doesn't have any payload capability once it gets configured into a higher end CrewCab. e.g. Laramie 4x4 1,230lbs to be exact isn't much payload.

Here is what I came up with approx. 550lbs of tongue weight alone leaves me with only 680 lbs of payload. I usually put a cap on my trucks, so that is an easy 200-250lbs. Now I'm down to 430 lbs and I still need to add myself, wife and son. If we are going away for the weekend there still needs to be some luggage added. The 1500 just doesn't work.

Olli

No offense but it sounds like you're trying to convince yourself you need the 2500. I tow a 6500 lb travel trailer300-400 lbs in bed, wife and i in cab along with all the other junk you seem to need. 2018 1500, 5.7. Towing it thinks I'm wealthy, of coarse I don't poke around 60 mph, I run 70+...sometimes a lot + on the interstate. If I keep it under 70 i MIGHT get 8-9 mpg best. Tows like a dream, handles great with load leveling hitch. BUT for the other 48-49 weeks a yr I really enjoy the 17-18 mpg city and 21-22 highway. Everyone thats honest seem to get about the same towing with 2500 but only around 11 not towing. Until I buy something significantly heavier.....it's the 1500 for me. JMO

 

[dhay13]

Honesty? I just made a 300 mile trip in my 2018 2500 6.4 CCSB 4.10's 4x4 and got 16.8 hand calculated with the cruise set at about 67 MPH. I get about 12 in town. Towing our 9000lb boat I get about 9 MPG. My son has the exact same truck as me and towed his 8500lb camper 1500 miles to North Dakota and back and got about 9 MPG.

I certainly wouldn't be towing 70+ MPH, especially with a 1500. You are asking for trouble there.

 

[Sandevino]

No offense but it sounds like you're trying to convince yourself you need the 2500. I tow a 6500 lb travel trailer300-400 lbs in bed, wife and i in cab along with all the other junk you seem to need. 2018 1500, 5.7. Towing it thinks I'm wealthy, of coarse I don't poke around 60 mph, I run 70+...sometimes a lot + on the interstate. If I keep it under 70 i MIGHT get 8-9 mpg best. Tows like a dream, handles great with load leveling hitch. BUT for the other 48-49 weeks a yr I really enjoy the 17-18 mpg city and 21-22 highway. Everyone thats honest seem to get about the same towing with 2500 but only around 11 not towing. Until I buy something significantly heavier.....it's the 1500 for me. JMO

Snap a pic of the sticker in your drivers door jamb and post it up as I’m curious about your numbers.

This link gives us the specs, payload specifically, about the 2018 1500’s.
https://www.ramtruck.ca/documents/ramtruck/specifications/2018-ramtruck-1500ds-specifications-en.pdf

Depending on how it’s equipped, the min/max payload numbers are 1380# / 1790#.


In your example, let’s assume your trailer is loaded at 6500# (10% tongue weight 650#) you and your wife (400# total as a guess), 400# of weight in bed and other gear (100#) you’re pushing your payload if not exceeding it. If your trailer is unloaded at 6500# you need to factor the loaded weight to get your accurate tongue weight.

Heres’s the math..

650 + 400 + 400 + 100 = 1550# payload at 10% tongue weight

Have you weighed your rig on a CAT scale? I’d love to see the weigh slip.

I tow a travel trailer that weighs 7600# dry (with an 11% tongue weight of 835#). If I use your other numbers, my payload would be 1735#. While you may be able to tow it, you’re pushing your payload.

1500# payload is not something I’d be comfortable with in a half ton. Getting it rolling is one thing. Stopping is another problem all together.

For comparison, my 2500 has 3100# of payload.

 

[dhay13]

Snap a pic of the sticker in your drivers door jamb and post it up as I’m curious about your numbers.

This link gives us the specs, payload specifically, about the 2018 1500’s.
https://www.ramtruck.ca/documents/ramtruck/specifications/2018-ramtruck-1500ds-specifications-en.pdf

Depending on how it’s equipped, the min/max payload numbers are 1380# / 1790#.


In your example, let’s assume your trailer is loaded at 6500# (10% tongue weight 650#) you and your wife (400# total as a guess), 400# of weight in bed and other gear (100#) you’re pushing your payload if not exceeding it. If your trailer is unloaded at 6500# you need to factor the loaded weight to get your accurate tongue weight.

Heres’s the math..

650 + 400 + 400 + 100 = 1550# payload at 10% tongue weight

Have you weighed your rig on a CAT scale? I’d love to see the weigh slip.

I tow a travel trailer that weighs 7600# dry (with an 11% tongue weight of 835#). If I use your other numbers, my payload would be 1735#. While you may be able to tow it, you’re pushing your payload.

1500# payload is not something I’d be comfortable with in a half ton. Getting it rolling is one thing. Stopping is another problem all together.

For comparison, my 2500 has 3100# of payload.

Yeah he definitely has to be pushing the payload. My 2013 1500 Express payload was about 1350lbs. It was a 4x4 QC but mostly stripped down being an express. My 2018 2500 payload is 2973lbs