Pentastar vs Hemi, which should you choose?

[Huliodude]

Without the 3-way electronic valve, the ATF heater on the ZF8 is able to see full coolant flow all the time. The thermostat is on the ATF side of the heater. ATF either goes through the heater or bypasses it internally.

No that can’t be right. There are no coolant lines at all going to the transmission anymore. There’s only atf fluid lines that flows atf to the top of the a/c condenser which uses a portion of it as a trans cooler. The fluid only flows when the thermostat near the trans opens to cool it down.

 

[PoMansRam]

No that can’t be right. There are no coolant lines at all going to the transmission anymore. There’s only atf fluid lines that flows atf to the top of the a/c condenser which uses a portion of it as a trans cooler. The fluid only flows when the thermostat near the trans opens to cool it down.

You're saying your Ram does not have a fluid heater bolted to the transmission?

Maybe this is something on newer models, but I have never heard of a ZF8 in a Ram 1500 that does not have a fluid heater.

My 2019 classic hemi w/ ZF8 has a plastic coupling in place where the coolant 3-way valve was on earlier models. There's a few threads on this on this site. There's two hoses tied into the coupling. Here's a pic I took of mine a year or so ago. The coupling is towards the lower right.

 

[Huliodude]

You're saying your Ram does not have a fluid heater bolted to the transmission?

Maybe this is something on newer models, but I have never heard of a ZF8 in a Ram 1500 that does not have a fluid heater.

My 2019 classic hemi w/ ZF8 has a plastic coupling in place where the coolant 3-way valve was on earlier models. There's a few threads on this on this site. There's two hoses tied into the coupling. Here's a pic I took of mine a year or so ago. The coupling is towards the lower right.

View attachment 484640

My truck hoses look exactly like yours. Those 2 long hoses in the centre of the picture go straight into the cabin heater core. Those are what used to go into 3 three way coolant valve, to be either sent to the transmission, the cabin heater core, or a variation of both depending on varying factors. The 2 hoses coming off that coupling on the on the lower rad hose simply go to the oil filter housing, and I believe that's an engine oil-to-coolant heat exchanger.



This is the parts diagram for our trucks. These lines carry trans fluid to/from the trans cooler that's part of the AC condenser.



This is the diagram for the older 4th gens that have both the warmer and the cooler. We don't have any of the coolant lines, such as #1, #2, #3, #4, or #5. The heat exchanger #7, is probably not on the side of our transmission either. I can't confirm that as there's too much ****** snow on my driveway to slide the creeper around. Below are the descriptions of #1 through #5 that I think we don't have on our newer classic trucks, along with associated parts.

 

[PoMansRam]

@Huliodude, I do hope you are right with this, because how sweet is it to not have more stuff that leaks and fails. Can any other newer classic or 5th gen owner confirm the lack of ATF heater?

I swear I've seen the ATF heater on the side of the trans on my 2019 classic while rolling around underneath fluid filming / woolwaxing it, but I could be mixing it up with my previous 2017 Ram 1500 pentastar, that had the 3-way, etc.

I'd go out there in the dark now if it weren't pouring rain and then supposed to snow 1-2 feet again tonight..

 

[Huliodude]

@Huliodude, I do hope you are right with this, because how sweet is it to not have more stuff that leaks and fails. Can any other newer classic or 5th gen owner confirm the lack of ATF heater?

I swear I've seen the ATF heater on the side of the trans on my 2019 classic while rolling around underneath fluid filming / woolwaxing it, but I could be mixing it up with my previous 2017 Ram 1500 pentastar, that had the 3-way, etc.

I'd go out there in the dark now if it weren't pouring rain and then supposed to snow 1-2 feet again tonight..

You're right about that, the lack of parts definitely points to a less complex system and less points of failure, however at the cost of cold start fuel economy. I would say that's worth it if you are keeping the vehicle long term.

I heard the 5th gens not only have the trans warmer, but also a rear differential oil warmer. The rear cover has a water jacket that flows hot coolant through it to warm the diff oil. Despite these efforts, the fact that it's a lighter truck, and also has the updated 8HP75 with the slightly wider gear spread, many guys on here say their 5th gen burns more fuel than their 4th gen. No idea what that's all about.

 

[hemihustlin]

But have fun changing those 16 spark plugs, and doing oil changes on your Hemi. You can walk out each morning to see that Hemi badge on the side, and really feel like a man.

darn tootin! my output shaft gets harder and longer every time my eyes read the word hemi! you dont want to know what happen on a cold start!

but seriously some of you guys should be looking at a gender swap if you think that changing spark plugs and oil on a hemi is THAT hard. its not. a minor inconvenience at best.
if you would like to try something thats very poorly designed buy a f150 with the 5.4 mod motor and let me know how the spark plug and oil change goes
or extracting broken manifold studs on a winnabago with the ford v10 6.8l
hell doing anything on a econoline under the doghouse

theres literally a whole world of things worse to work on than a hemi! thats why I bought one haha

so stop yall bellyaching and let the people enjoy their hemis! if you dont have the skills to maintain one that doesnt mean others dont!

 

[Dusty]

You're right about that, the lack of parts definitely points to a less complex system and less points of failure, however at the cost of cold start fuel economy. I would say that's worth it if you are keeping the vehicle long term.

I heard the 5th gens not only have the trans warmer, but also a rear differential oil warmer. The rear cover has a water jacket that flows hot coolant through it to warm the diff oil. Despite these efforts, the fact that it's a lighter truck, and also has the updated 8HP75 with the slightly wider gear spread, many guys on here say their 5th gen burns more fuel than their 4th gen. No idea what that's all about.

The cooled rear differential is part of an option package that includes a 9 1/2 ring gear. Rear diff cooling is not available on the 9 1/4 ZF.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 064366 miles.

 

[Dusty]

darn tootin! my output shaft gets harder and longer every time my eyes read the word hemi! you dont want to know what happen on a cold start!

but seriously some of you guys should be looking at a gender swap if you think that changing spark plugs and oil on a hemi is THAT hard. its not. a minor inconvenience at best.
if you would like to try something thats very poorly designed buy a f150 with the 5.4 mod motor and let me know how the spark plug and oil change goes
or extracting broken manifold studs on a winnabago with the ford v10 6.8l
hell doing anything on a econoline under the doghouse

theres literally a whole world of things worse to work on than a hemi! thats why I bought one haha

so stop yall bellyaching and let the people enjoy their hemis! if you dont have the skills to maintain one that doesnt mean others dont!

While helping my neighbor troubleshoot an engine performance problem this past summer, I couldn't believe how much plumbing criss-crosses the engine on his F-150. And except for the rear two plugs on my 5.7, getting the plugs out is a dream compared to his F-series. And I don't really see how difficult it is to change oil on my Hemi, either, and I do it in the driveway.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 064366 miles.

 

[tap4154]

darn tootin! my output shaft gets harder and longer every time my eyes read the word hemi! you dont want to know what happen on a cold start!

but seriously some of you guys should be looking at a gender swap if you think that changing spark plugs and oil on a hemi is THAT hard. its not. a minor inconvenience at best.
if you would like to try something thats very poorly designed buy a f150 with the 5.4 mod motor and let me know how the spark plug and oil change goes
or extracting broken manifold studs on a winnabago with the ford v10 6.8l
hell doing anything on a econoline under the doghouse

theres literally a whole world of things worse to work on than a hemi! thats why I bought one haha

so stop yall bellyaching and let the people enjoy their hemis! if you dont have the skills to maintain one that doesnt mean others dont!

I have a motorhome with a 2010 6.8 Ford V10 in it. I think by then they had the manifold bolt issue worked out, but maybe not. I'll knock on wood.

Hey if you love your Hemi that's fine by me. And it has nothing to do with having the skill to work on one. I just have better things to do then turn up the radio to hide the Hemi tick, and change 16 plugs, and buy an oil filter relocation kit

 

[tap4154]

Have fun pulling the manifold to change those 6 spark plugs !. I agree though the pentastar is a great engine. Even changing the air filter is a pia.

From what I've read it really isn't that difficult to remove the manifold, and changing the air filter is a piece of cake!

 

[huntergreen]

From what I've read it really isn't that difficult to remove the manifold, and changing the air filter is a piece of cake!

Couldn’t tell you , I let a mechanic do it. Air filter on my wrangler might be a bit different, but far more of a pia than the hemi.

 

[tap4154]

Couldn’t tell you , I let a mechanic do it. Air filter on my wrangler might be a bit different, but far more of a pia than the hemi.

It takes about 30 seconds to change the air filter on the Pentastar. No tools required, and it's on the far passenger side of the compartment, and very easy access. Just pop a few finger clips, lift the cover, take the old filter out and put the new one in, put the cover back on and push the clips back on. I could have done it faster than I wrote this post :0)

 

[PoMansRam]

While helping my neighbor troubleshoot an engine performance problem this past summer, I couldn't believe how much plumbing criss-crosses the engine on his F-150. And except for the rear two plugs on my 5.7, getting the plugs out is a dream compared to his F-series. And I don't really see how difficult it is to change oil on my Hemi, either, and I do it in the driveway.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33 gallon fuel tank, factory dual exhaust, 18” wheels. Build date: 03 June 2018. Now at: 064366 miles.

Agree. Based on the later model F150's I've seen under the hood of, ecoboost or othersiwe, the hemis are simple.

I find the oil filter to be easy to get to on my 2019 classic hemi once you're on your back, slid under there. It's just a bit messy, so you need some rags to wipe things down the best you can afterwards given oil runs all around the E-power steering system.

I find I have to slide further under, behind the right front wheel to get at the drain plug on the hemi, vs the distance you had to go for the pentastar powered Rams. The engine oil drain plug is positioned to the right side on the pentastar vs being centered under the truck on the hemi.

 

[hemihustlin]

Hey if you love your Hemi that's fine by me. And it has nothing to do with having the skill to work on one. I just have better things to do then turn up the radio to hide the Hemi tick, and change 16 plugs, and buy an oil filter relocation kit

I actually like the pentastar for a v6, I think its a fine motor. I just prefer hemi power! 16 relatively well placed plugs and a semi out of the way oil filter is not enough to turn me off of that. this one and my last hemi have never ticked so I dont know about that.

 

[PoMansRam]

No that can’t be right. There are no coolant lines at all going to the transmission anymore. There’s only atf fluid lines that flows atf to the top of the a/c condenser which uses a portion of it as a trans cooler. The fluid only flows when the thermostat near the trans opens to cool it down.

@Huliodude You made me do it. LOL. I threw a piece of cardboard on the snow and took a pic underneath my 2019 classic, hemi, that does not have the 3-way coolant valve. As I thought. I've still got the ATF heater on my 8hp70 as all do as far as I'm aware. If yours indeed does not have the ATF heater, out of curiosity, I'd like to see a pic.

The amount of road salt under my truck is depressing. I'm fluid filmed and woolwaxed, but still. Ugh..

 

[huntergreen]

It takes about 30 seconds to change the air filter on the Pentastar. No tools required, and it's on the far passenger side of the compartment, and very easy access. Just pop a few finger clips, lift the cover, take the old filter out and put the new one in, put the cover back on and push the clips back on. I could have done it faster than I wrote this post :0)

Different on my my wrangler and wife’s Cherokee.

 

[farout75]

I have had two RAM 1500 with the 3.6. IMO the RAM 1500 with the 3.6 is a light duty truck. Just driving up a steep hill on the freeway going West on Hwy 44 in Missouri headed to Springfield required to change gears to 6th just to keep up with traffic. Say nothing about towing a 4,000 lb trailer, the 3.6 with its 269 lbs of torque is very poor. The gas mpg is only 2 mpg more at best and not worth the frustration of having big diesel trucks pass you by.

 

[tap4154]

Agree. Based on the later model F150's I've seen under the hood of, ecoboost or othersiwe, the hemis are simple.

I find the oil filter to be easy to get to on my 2019 classic hemi once you're on your back, slid under there. It's just a bit messy, so you need some rags to wipe things down the best you can afterwards given oil runs all around the E-power steering system.

I find I have to slide further under, behind the right front wheel to get at the drain plug on the hemi, vs the distance you had to go for the pentastar powered Rams. The engine oil drain plug is positioned to the right side on the pentastar vs being centered under the truck on the hemi.

That's right, you don't even have to be under the truck to remove the drain plug on the Pentastar. You can reach it just lying down next to the right front wheel. By the way you can also change the oil filter in between oil changes if you want to, and not lose any oil.

 

[tap4154]

I have had two RAM 1500 with the 3.6. IMO the RAM 1500 with the 3.6 is a light duty truck. Just driving up a steep hill on the freeway going West on Hwy 44 in Missouri headed to Springfield required to change gears to 6th just to keep up with traffic. Say nothing about towing a 4,000 lb trailer, the 3.6 with its 269 lbs of torque is very poor. The gas mpg is only 2 mpg more at best and not worth the frustration of having big diesel trucks pass you by.

Absolutely no doubt if you're going to do some heavy towing, you're better off with the Hemi, or a Cummings. But just for using it as a work and sport truck, the 3.6 really does well. I have a Class C motorhome with a V10, so I won't be towing a trailer with my truck.

 

[tap4154]

Different on my my wrangler and wife’s Cherokee.

The Jeeps have a much smaller engine compartment than the Ram does. It really could not be any easier to change the Ram air filter.