8hp70 heater bypass

[Wild one]

Hey guys I was easier on it initially than normal and second pic of temps reflect that. I’m goin to wrap the crossover with the left over wrap from my 4th Gen to see if that helps. So far not a drastic diff from before tho I only have a couple k miles in current truck.

If you have a pair of hose pinchers,try clamping off the heater hoses feeding the heat exchanger to see if that makes a differance. I was under the impression the 8HP75 used the same heat exchanger as the 8HP70 does,but maybe they did change it up somewhat,so i'm wondering if you might have to kill the coolant flow to it also, to reap the full benefits of Jesse's plug

 

[joesstripclub]

Thanks power was not my goal, cooler temps are. Though empty with 3.92 and quad cab it runs like a ***** ape already lol. Ask the newer three series that thought I was racing him during my wot runs lol. He couldn’t hang

I’m just not seeing a drastic change in temps if any at all right now with this modified tstat in my 5th Gen 8hp75...

Edit: Deleted because I was confused.

 

[caulk04]

Stop spreading miss information. My part accomplishes the exact same end result as the full revmax kit, with less parts and less work.

 

[Wild one]

Stop spreading miss information. My part accomplishes the exact same end result as the full revmax kit, with less parts and less work.

I bought the overpriced RevMax kit and never used it,lol. If i was doing it again,i'd be buying your bypass plug Jesse,as it's alot less work to install,way cheaper to,and easily reversed if you ever have to reverse it and put the tranny back to stock.The way Khris and i did it,kills everything thermostat related,but in hindsight your plug would of been the smarter way to go.We were about a week to quick,lol.
Rick

 

[chrisbh17]

I bought the overpriced RevMax kit and never used it,lol. If i was doing it again,i'd be buying your bypass plug Jesse,as it's alot less work to install,way cheaper to,and easily reversed if you ever have to reverse it and put the tranny back to stock.The way Khris and i did it,kills everything thermostat related,but in hindsight your plug would of been the smarter way to go.We were about a week to quick,lol.
Rick

Reminds me that I have one of his replacements sitting here in my computer room. Its warm out in CT now, so I might get around to installing and seeing the temp change.

If it keeps it too cold in the winter, at least its not too hard to go back to stock.

 

[joesstripclub]

.

 

[crazykid1994]

How does your part block the heater? Is it not just a replacement for the thermostat?

It blocks transmission fluid from going through the heat exchange on the side of the transmission

 

[joesstripclub]

.

 

[crazykid1994]

The heat exchanger will still have coolant flowing to it which will still heat the fluid. The thermostat controls flow to the transmission cooler but does not stop the transmission fluid from flowing through the heat exchanger. That's why the Revmax kit has the plate and a couple guys experimented with installing plugs into the heat exchanger ports.

Wrong. Both Wildone and I have been in these heat exchangers. The thermostat directs fluid either between the heater or the radiator. It closes one port to open the other. Fluid does not consistently flow through the heater as you are saying.

 

[crazykid1994]

The heat exchanger will still have coolant flowing to it which will still heat the fluid. The thermostat controls flow to the transmission cooler but does not stop the transmission fluid from flowing through the heat exchanger. That's why the Revmax kit has the plate and a couple guys experimented with installing plugs into the heat exchanger ports.

The heater still gets coolant flow but no longer gets transmission fluid. The rev max kit uses a plate to block the heater from getting trans fluid but does not block coolant flow. Caulks piece does the exact same thing but easier By blocking the heater port and leaving the radiator port open without disassembling the entire assembly.

 

[joesstripclub]

Wrong. Both Wildone and I have been in these heat exchangers. The thermostat directs fluid either between the heater or the radiator. It closes one port to open the other. Fluid does not consistently flow through the heater as you are saying.

The heater still gets coolant flow but no longer gets transmission fluid. The rev max kit uses a plate to block the heater from getting trans fluid but does not block coolant flow. Caulks piece does the exact same thing but easier By blocking the heater port and leaving the radiator port open without disassembling the entire assembly.

I went back and re-read the huge thread and it makes more sense now. There was a lot of terminology in there and I misunderstood how the thermostat block worked. For some reason I got in my head they were separate systems that were heating and cooling independently. That's what happens when you read 100 forum pages too quickly.

 

[caulk04]

No harm, no foul. Just wanted to nip it in the bud. That's why we're all in here.

 

[hawsk99gt]

Mine worked! Thanks, Jesse!

 

[MRFREEZE57]

the Ram is the first truck have owned with an automatic but I remember years back it was very common to install an auxiliary cooler for the transmission for a truck. is there any negatives to running too cool of fluid temps in an automatic when the weather is cold?

 

[HvyDuty]

Mine worked! Thanks, Jesse!

What temps are you seeing before vs. after? Thanks

 

[HEMIMANN]

the Ram is the first truck have owned with an automatic but I remember years back it was very common to install an auxiliary cooler for the transmission for a truck. is there any negatives to running too cool of fluid temps in an automatic when the weather is cold?

For ATF, no. Transmissions don't deal with combustion blow by of engines, where vaporizing combustion water is important. Miniscule increase in fuel consumption due to higher viscous friction is irrelevant.

Even though I run a 66RFE, the principles are the same for any automatic transmission - holding bulk oil temp to 140F or so is critical to full service life of the oil and the transmission. Oil oxidation and varnishing are the biggest threats to automatic transmissions.

 

[MRFREEZE57]

For ATF, no. Transmissions don't deal with combustion blow by of engines, where vaporizing combustion water is important. Miniscule increase in fuel consumption due to higher viscous friction is irrelevant.

Even though I run a 66RFE, the principles are the same for any automatic transmission - holding bulk oil temp to 140F or so is critical to full service life of the oil and the transmission. Oil oxidation and varnishing are the biggest threats to automatic transmissions.

but lets say in the winter time is it good or bad that lets say the temp never goes over 100deg?

 

[Wild one]

but lets say in the winter time is it good or bad that lets say the temp never goes over 100deg?

The cars and heavy duty trucks don't pre-heat the tranny fluid,and they work fine in the winter.My wifes 2019 6.4 Challenger will take 50 miles to warm up to 110F with outside temps 30/32F if you're not beating on it.I can go to the city and back with it on a day where the outside temps are high 20's low 30's and it might get to 100F on the tranny temp.I'm in Alberta,little north and east of you,and you guys get mild winters compared to us,lol

 

[hawsk99gt]

What temps are you seeing before vs. after? Thanks

I was getting 245 - 250* at 70mph highway driving. At 85mph I got up to 275* and got a warning light on telling me to either slow down or it was going to shut down. Now at 75mph I am getting 150* and while loaded up with half a pallet of ceramic tile. I would say the highest it got while driving it after the swap was 160*.

 

[HvyDuty]

I was getting 245 - 250* at 70mph highway driving. At 85mph I got up to 275* and got a warning light on telling me to either slow down or it was going to shut down. Now at 75mph I am getting 150* and while loaded up with half a pallet of ceramic tile. I would say the highest it got while driving it after the swap was 160*.

Damn nice. Well I got to 195 beating the hell out of it after the swap. I don’t think I’ve seen over 200 even towing my 5th wheel BEFORE the swap. I guess I’m doin better than I thought but was hope for numbers like yours after it.