8hp70 heater bypass

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dc435911

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I debated on doing something similar but drilling it out to a -12an and running new an line all the way to the front and putting in a standalone radiator for the trans with a 160° in line bypass thermostat
That's similar to my long term plan when I have more time. The homes are sized for -8an on the side of the trans case and can be drilled larger. Just tap for -8an and start plumbing.
 

dc435911

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I debated on doing something similar but drilling it out to a -12an and running new an line all the way to the front and putting in a standalone radiator for the trans with a 160° in line bypass thermostat
City driving takes around 10-15mins in 80+ ambient. On highway it takes over 30mins.
 

BlownGP

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So does it run cooler
City driving takes around 10-15mins in 80+ ambient. On highway it takes over 30mins.

So does it run cooler?
Looks good though.

I assume a bunch of fluid came out when you took those lines off?
 

18GSMRam

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Anyone know what the size of the O-Ring is? Mine is leaking from the bypass area.
 

dc435911

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So does it run cooler


So does it run cooler?
Looks good though.

I assume a bunch of fluid came out when you took those lines off?
Runs cooler on the interstate 160-170f. City driving is still 180-185f but cools off on the interstate. It wont run as cool as a thermostat bypass will but I want to see how the winter goes first with this setup.

I lost a little under a quart of trans fluid. Easy enough to top off following the refill procedure.
 

BlownGP

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Runs cooler on the interstate 160-170f. City driving is still 180-185f but cools off on the interstate. It wont run as cool as a thermostat bypass will but I want to see how the winter goes first with this setup.

I lost a little under a quart of trans fluid. Easy enough to top off following the refill procedure.

Interesting.
 

HTXRamExp

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Well after all my drama of getting the thermostat out initially. I did end up getting caulks piece installed.

I didn't feel comfortable with the amount of fluid I lost, so I grabbed a quart from the dealer to top off.

Following the fill procedure provided by @Wild one , I was surprised how high I had to jack the rear end to get the pan level.

Edit: I'm really surprised, researching all the 8speed fill procedures I see on YouTube primarily, no one mentions or does adjust the truck to get the pan level.

The fill plug location is a PITA. I also had a bonehead moment, when I went to crack and back off the fill plug prior to going through the procedure and accidentally backed it off too far and took another slight bath in trans fluid and soaked my freshly wrapped crossover pipe. D'oh!

Ambient temperature was right around 84* so used a fan to help cool down the trans prior, but I assume I went over the 86* temp threshold.

Ran through the procedure and topped off the trans fluid.

8873E5AF-8B3C-4E62-B55D-EDB262C20E5E.jpeg
2019 Ram 1500 Classic, 5.7l, 8speed, 4x4, crew cab stock truck temps during mostly flat highway drive across Texas at ~85mph w/ 79*F ambient temp. Redline 5w-30 oil w/ 65XXmi and Royal Purple 10-48 filter.
09533079-5632-4059-9B0D-B2D26826D06F.jpeg
Mods: 180* coolant thermostat, caulk trans thermostat bypass, AGS deleted, stock v8 fans deleted, v6 fan installed, a/c on.
Highest temps (+/- a couple deg) I observed driving through some hillier parts of Texas, cruise at 85mph, 99*F ambient temperature according to truck.
redline 5w-30 oil w/ ~3k miles, Royal purple 20-820 filter.
C14969C2-E00A-4038-9C76-DF6D67964027.jpeg
While driving mostly flat highway across Texas, ambient temp f/ 85-100*F, at 75-85mph these were generally the average temps I observed.
 

Nick14

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I was surprised also with how high it had to go to get level. I had the rear about a foot in the air and had to loosen up the trans cross member jack up the trans. to get an even bubble on my level. Nick
 

BlownGP

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Mods: 180* coolant thermostat, caulk trans thermostat bypass, AGS deleted, stock v8 fans deleted, v6 fan installed, a/c on.
Highest temps (+/- a couple deg) I observed driving through some hillier parts of Texas, cruise at 85mph, 99*F ambient temperature according to truck.
redline 5w-30 oil w/ ~3k miles, Royal purple 20-820 filter.

While driving mostly flat highway across Texas, ambient temp f/ 85-100*F, at 75-85mph these were generally the average temps I observed.

Did you notice a cooling difference with the V6 fan.

I deleted them on my orange Ram because the stock e-fan died and was a good time to do it. It seemed like it cooled down faster but don't really now.

Was going to do it on my blue truck but with the 180 thermo and AGS deleted it seems to stay pretty cool. So not sure if I am going to do it now.
 

crazykid1994

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Did you notice a cooling difference with the V6 fan.

I deleted them on my orange Ram because the stock e-fan died and was a good time to do it. It seemed like it cooled down faster but don't really now.

Was going to do it on my blue truck but with the 180 thermo and AGS deleted it seems to stay pretty cool. So not sure if I am going to do it now.
For more extreme towing/hauling I would stick to the clutch fan since that gives you 2 fans pulling air through. If you aren’t maxing the truck I definitely feel the v6 fan is awesome and helped free up some low end power for me and I’ve had 0 issues with cooling. 190° tstat in my truck. Lifted with 35s and go off-road on trails here and there and have also towed an enclosed trailer loaded and have had no issues.
 

HTXRamExp

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Did you notice a cooling difference with the V6 fan.

I deleted them on my orange Ram because the stock e-fan died and was a good time to do it. It seemed like it cooled down faster but don't really now.

Was going to do it on my blue truck but with the 180 thermo and AGS deleted it seems to stay pretty cool. So not sure if I am going to do it now.
The v6 fan hasn't had any issues keeping temperatures in check while moving/with the a/c on (waiting to receive my unlocked PCM still). One time during my drive I hit stop-n-go traffic and I turned the a/c off to see how quickly temps would rise. They gradually got up to ~215* then I turned the a/c back on, still in stop-n-go traffic and the fan brought temps back down to 190 within a couple minutes.
 

Wild one

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You guys are running warmer then mine.Had mine out today,our ambient air temp was between 83 to 86F,put 225 miles on the truck,and the highest i seen was 138F on the tranny,and that was after a 5 mile stint at wot,just to see what the old girl still had in her,still has lots,lol.With-in 2 miles after slowing back down to 60mph,it had dropped back down to 128F. But my truck is running a 160F T-stat,middle AGS slats removed,PPE transmission pan,with the cross-over exhaust pipe double header wrapped and the transmissions heat exchanger is totally deleted. I sure like the way it shifts at the cooler temps,and how good it'll hold hills in 8th ,hills that used to make it downshift to 7th with the cruise on,it'll hold 8th for the most part now
 

joesstripclub

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I was surprised also with how high it had to go to get level. I had the rear about a foot in the air and had to loosen up the trans cross member jack up the trans. to get an even bubble on my level. Nick
I got the rear of the truck as high as my jack would go and I was still out of level a bit but close enough. I think I would need a 4x4 on top of my jack to make it fully level. I'm really not sure how you are supposed to get it safely to level unless the truck is sitting downhill and you have some really good wheel chocks.
 

HTXRamExp

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I got the rear of the truck as high as my jack would go and I was still out of level a bit but close enough. I think I would need a 4x4 on top of my jack to make it fully level. I'm really not sure how you are supposed to get it safely to level unless the truck is sitting downhill and you have some really good wheel chocks.
Same, I ran out of jack. The bubble on my level was just within the lines, figured it was close enough.
 

BlownGP

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For more extreme towing/hauling I would tick to the clutch fan since that gives you 2 fans pulling air through. If you aren’t maxing the truck I definitely feel the v6 fan is awesome and helped free up some low end power for me and I’ve had 0 issues with cooling. 190° tstat in my truck. Lifted with 35s and go off-road on trails here and there and have also towed an enclosed trailer loaded and have had no issues.

Yeah, no towing or hauling for me. If I did it wouldn't be that much.

I guess I will do it someday down the line. I read on here somebody claimed the clutch fan will make the water go out prematurely. That was another reason for me do the swap.

The v6 fan hasn't had any issues keeping temperatures in check while moving/with the a/c on (waiting to receive my unlocked PCM still). One time during my drive I hit stop-n-go traffic and I turned the a/c off to see how quickly temps would rise. They gradually got up to ~215* then I turned the a/c back on, still in stop-n-go traffic and the fan brought temps back down to 190 within a couple minutes.

See 215 seems pretty high with a 180 t-stat. I know you are not tuned, but mine as never gotten that high with a 180 t-stat. I'm not tuned either.
 

BlownGP

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You guys are running warmer then mine.Had mine out today,our ambient air temp was between 83 to 86F,put 225 miles on the truck,and the highest i seen was 138F on the tranny,and that was after a 5 mile stint at wot,just to see what the old girl still had in her,still has lots,lol.With-in 2 miles after slowing back down to 60mph,it had dropped back down to 128F. But my truck is running a 160F T-stat,middle AGS slats removed,PPE transmission pan,with the cross-over exhaust pipe double header wrapped and the transmissions heat exchanger is totally deleted. I sure like the way it shifts at the cooler temps,and how good it'll hold hills in 8th ,hills that used to make it downshift to 7th with the cruise on,it'll hold 8th for the most part now

I noticed that on a recent road trip, while hitting hills in the east Texas and going on over passes. It wants to always downshift to 7th.
I was like damn, my old 5 speed never downshifted that much. lol
 

EdGs

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I got the rear of the truck as high as my jack would go and I was still out of level a bit but close enough. I think I would need a 4x4 on top of my jack to make it fully level. I'm really not sure how you are supposed to get it safely to level unless the truck is sitting downhill and you have some really good wheel chocks.
When I did my fluid/filter change, I used a 4x4 on top of the floor jack. Worked like a charm.

I would like to drain and put some more fresh fluid in as I have put about 14k miles on it since Jan. 1, waiting for finances to ease up a bit.
 

heefageLA

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I have one of these coming and look forward to my temps not being 190* everyday, and not even towing anything.

I also put in a 190* Thermostat and removed my Grill Shutters but screwed up by pulling all but the center one connected to the motor. Now I have a Check Engine light wont go away and dont think I can "reinstall" the shutters... Its crazy how difficult they make the 5th gen grill to be removed. I could pop my 4th gen grill off in about 10 minutes, but im not possibly destroying my new 5th gen just to get at the grill shutters from the front.
 

BlownGP

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I have one of these coming and look forward to my temps not being 190* everyday, and not even towing anything.

I also put in a 190* Thermostat and removed my Grill Shutters but screwed up by pulling all but the center one connected to the motor. Now I have a Check Engine light wont go away and dont think I can "reinstall" the shutters... Its crazy how difficult they make the 5th gen grill to be removed. I could pop my 4th gen grill off in about 10 minutes, but im not possibly destroying my new 5th gen just to get at the grill shutters from the front.

That reminds of when Jeremy at RetroShop got his first 5th gen to take apart the headlights. I think it took him half a day just to remove everything to just get to the headlights. lol

Another reason I stuck with the 4th gen. I just about hot to take everything apart and most of it is pretty easy.
 
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