RevMax 8 speed thermostat bypass

[caulk04]

https://www.ramforum.com/threads/8hp70-heater-bypass.172998/#post-2440741

The part I'm making will accomplish the same thing as the revmax kit, but you won't have to remove the heater unit to block it off. You'll only have to pull the plug and thermostat, which is also required in their kit. It forces the system to function as if the fluid is hot and the thermostat is open.

 

[seabrook]

Being as how ZF is Germany based,i'd lay odds the transmission has been engineered to handle -20 temps while being abused and still live. They'll have planned around the average driver who doesn't pay any attention to engine /oil or tranny temps before they start beating on the vehicle. We're a select few,who do pay attention to temps,the majority of owners don't,you could even do a poll on here to find out how many guys actually have the evicc on the temps and not the speedo,and it's probably more on the speedo then we think.My truck is always on the temps,but i'm always amazed at the amount of guys who have the evicc on the speedo

i do lol i wait for oil temps to go over -122 the other day i got on my truck with the oil temps below-122 and i cringed it has been running for at least 5 minutes though

 

[Musky Mike]

https://www.ramforum.com/threads/8hp70-heater-bypass.172998/#post-2440741

The part I'm making will accomplish the same thing as the revmax kit, but you won't have to remove the heater unit to block it off. You'll only have to pull the plug and thermostat, which is also required in their kit. It forces the system to function as if the fluid is hot and the thermostat is open.

Thanks, I replied to that thread.

 

[Bigskyroadglide]

Ive been following this thread for the last few days. Thought I would post up my 8 speed temps.

I drove from Virginia to Tennessee last night, here's a photo about 200 miles in.

RCSB, RWD, supercharged 5.7 with 3.92



Once warm, I rarely see more than 160

 

[Wild one]

Ive been following this thread for the last few days. Thought I would post up my 8 speed temps.

I drove from Virginia to Tennessee last night, here's a photo about 200 miles in.

RCSB, RWD, supercharged 5.7 with 3.92

View attachment 236673

Once warm, I rarely see more than 160

If that's a stock HP70,you definitely have a unicorn on your hands,as most of them run 180+ tranny temps.Were you the guy that found that truck on a lot a bit ago? If so i'd almost wonder if the tranny thermostat has been played with before you bought it.

 

[Bigskyroadglide]

Yup, that's me.

I don't know if someone has modified the transmission or not. Based on what I've found with the truck overall, I'm gonna say nothing has been touched.

I changed rear diff fluid today, looked like factory fill. Changed brake fluid today, almost as dark as engine oil. Never been touched.

Engine has used no oil in 2400 miles. But it's dark, so I'm changing it at 3k. Suspect it was on a steady diet of dino prior to my ownership.

I've had all 4 wheels off and found stock brakes. Tires were stock when new, at 43k, they are ready to be changed.

Just about everything I've found is stock except for the supercharger.

Not saying I know but suspect based on everything thing I've found, trans is stock.

I have verified the heater block is attached to the side of the transmission

 

[Wild one]

Yup, that's me.

I don't know if someone has modified the transmission or not. Based on what I've found with the truck overall, I'm gonna say nothing has been touched.

I changed rear diff fluid today, looked like factory fill. Changed brake fluid today, almost as dark as engine oil. Never been touched.

Engine has used no oil in 2400 miles. But it's dark, so I'm changing it at 3k. Suspect it was on a steady diet of dino prior to my ownership.

I've had all 4 wheels off and found stock brakes. Tires were stock when new, at 43k, they are ready to be changed.

Just about everything I've found is stock except for the supercharger.

Not saying I know but suspect based on everything thing I've found, trans is stock.

I have verified the heater block is attached to the side of the transmission

I'd lays odds the thermostat on that tranny has been tinkered with,or else the temp sensor is haywire.No way it's going to run at 152,when the tranny thermostat on a stock 8 speed doesn't open till it hits 180 degrees,so something is up with your tranny.Next time you're under it,look real close at the gap between the heat exchanger and the cooler bypass part of the thermal unit.You're looking for a thin flat plate about an 1/8" thick.Also look and see if it has a brass plug where the thermostat goes.

 

[Bigskyroadglide]

Ok, will do

 

[Different Drummer]

Ok, will do

Waiting with curiosity that is killing me!! I had to drive 40 miles each way yesterday to get my
Hung -pung- flu vaccine and mine ran between 180 and 190 depending on the type of driving.
Lower on the highway and higher in the city. OAT was 44 degrees. If someone went so far as to supercharge the engine they probably had the mechanical aptitude to recognize the rather warmish transmission fluid temps and decided to take corrective action of some sorts.

 

[Bigskyroadglide]

Alright, see multiple pics below, I don't see any brass











Ignore the fluid leak, I was fluid filming today and got some on the transmission

 

[Bigskyroadglide]

Here's the part number

 

[caulk04]

Interesting. Definitely a stock plug on the thermostat housing. How many miles does it take to go from cold start to 150 where it levels out?

A quick Google of the part number shows it was used only on 13/14 trucks and was replaced by another number, not just a new suffix (AB, AC etc) as is normal for revision changes in Dodge parts.

 

[Bigskyroadglide]

I drive 16 miles to work one way, by the time I get there in stop and go traffic. Avg speed 45 mph, trans temp has hit 190 and started to drop into the 170s. It takes about 50 miles to level out at 150.

 

[crazykid1994]

I drive 16 miles to work one way, by the time I get there in stop and go traffic. Avg speed 45 mph, trans temp has hit 190 and started to drop into the 170s. It takes about 50 miles to level out at 150.

The fact that it makes it to 190 then starts lowering to 170 and to 150 almost sounds like a faulty tstat. Like either it’s sticky and when it opens it’s not opening 100% and it’s not fluctuating between open and closed to regulate temps. The tstat is rated at 176° according to everything I’ve seen online.

 

[Bigskyroadglide]

My opinion after driving the truck almost 3,000 miles, it's not mechanical and I don't think the thermostat is sticking. I think it has something to do with the program from Edelbrock for the supercharger in conjunction with having an intercooler and an electronic water pump that keeps the water circulating to cool the supercharger

Nothing indicates that the truck is doing anything other than as it's designed. As I said in previous post, except for the supercharger the truck appears to be 100% stock meaning I don't think anything else was done to it when they installed the supercharger. I do know in talking to Edelbrock that the PCM was sent in and they updated it so their custom program could be installed. I do know the supercharger has a massive intercooler that sits in the front of the truck and I do know that you can't take the active shutters off because it sets a code I tried. So in conclusion at this point I'm assuming that it's functioning as designed to work with the supercharger. I do also know that if engine oil temp goes down from 210 trans temp tends to creep up but never over 160.

There's a whole lot of piping associated with the intercooler the electric water pump and additional hoses under the hood. They're all preformed they're all rubber and they all connect. I'm wondering if Edelbrock hasn't figured out a way to keep things within certain parameters to honor the warranty that they give out with each supercharger purchase. This is all supposition on my part as I don't have a technical answer.

I have not pushed the truck hard except on a couple of occasions as I've been working on the rear suspension and it still has the two-piece drive shaft. The suspension is now complete and I have no issues with it. The two-piece driveshaft will be replaced in the next two months, once that happens I'll be able to push the truck past 105 and we'll see if the temps change Right now I suspect engine oil temp will go up, engine coolant temp will go up, and trans temp will stay the same in the 150s. My thoughts

 

[Wild one]

My opinion after driving the truck almost 3,000 miles, it's not mechanical and I don't think the thermostat is sticking. I think it has something to do with the program from Edelbrock for the supercharger in conjunction with having an intercooler and an electronic water pump that keeps the water circulating to cool the supercharger

Nothing indicates that the truck is doing anything other than as it's designed. As I said in previous post, except for the supercharger the truck appears to be 100% stock meaning I don't think anything else was done to it when they installed the supercharger. I do know in talking to Edelbrock that the PCM was sent in and they updated it so their custom program could be installed. I do know the supercharger has a massive intercooler that sits in the front of the truck and I do know that you can't take the active shutters off because it sets a code I tried. So in conclusion at this point I'm assuming that it's functioning as designed to work with the supercharger. I do also know that if engine oil temp goes down from 210 trans temp tends to creep up but never over 160.

There's a whole lot of piping associated with the intercooler the electric water pump and additional hoses under the hood. They're all preformed they're all rubber and they all connect. I'm wondering if Edelbrock hasn't figured out a way to keep things within certain parameters to honor the warranty that they give out with each supercharger purchase. This is all supposition on my part as I don't have a technical answer.

I have not pushed the truck hard except on a couple of occasions as I've been working on the rear suspension and it still has the two-piece drive shaft. The suspension is now complete and I have no issues with it. The two-piece driveshaft will be replaced in the next two months, once that happens I'll be able to push the truck past 105 and we'll see if the temps change Right now I suspect engine oil temp will go up, engine coolant temp will go up, and trans temp will stay the same in the 150s. My thoughts

There's nothing the tune will do to affect the tranny temp,the tranny thermostat is mechanical,not electrical. It sure looks like it hasn't been tampered with that's for sure,which leads me down the same thought path as CrazyKid,the thermostat might be a little sticky or the temp sensor is out of sync. I tested the thermostat in a pot of boiling water and it doesn't start to open till right around 180F,and starts closing back up about 175F.

 

[Wild one]

Interesting. Definitely a stock plug on the thermostat housing. How many miles does it take to go from cold start to 150 where it levels out?

A quick Google of the part number shows it was used only on 13/14 trucks and was replaced by another number, not just a new suffix (AB, AC etc) as is normal for revision changes in Dodge parts.

My 14 is the same part number except mines a AC revision

 

[Bigskyroadglide]

You have way more experience with this than I do I'm just reporting what I see and how the truck performs. I don't know and I'm still learning on this process give me another couple of months and I might have a different theory.

 

[crazykid1994]

My opinion after driving the truck almost 3,000 miles, it's not mechanical and I don't think the thermostat is sticking. I think it has something to do with the program from Edelbrock for the supercharger in conjunction with having an intercooler and an electronic water pump that keeps the water circulating to cool the supercharger

Nothing indicates that the truck is doing anything other than as it's designed. As I said in previous post, except for the supercharger the truck appears to be 100% stock meaning I don't think anything else was done to it when they installed the supercharger. I do know in talking to Edelbrock that the PCM was sent in and they updated it so their custom program could be installed. I do know the supercharger has a massive intercooler that sits in the front of the truck and I do know that you can't take the active shutters off because it sets a code I tried. So in conclusion at this point I'm assuming that it's functioning as designed to work with the supercharger. I do also know that if engine oil temp goes down from 210 trans temp tends to creep up but never over 160.

There's a whole lot of piping associated with the intercooler the electric water pump and additional hoses under the hood. They're all preformed they're all rubber and they all connect. I'm wondering if Edelbrock hasn't figured out a way to keep things within certain parameters to honor the warranty that they give out with each supercharger purchase. This is all supposition on my part as I don't have a technical answer.

I have not pushed the truck hard except on a couple of occasions as I've been working on the rear suspension and it still has the two-piece drive shaft. The suspension is now complete and I have no issues with it. The two-piece driveshaft will be replaced in the next two months, once that happens I'll be able to push the truck past 105 and we'll see if the temps change Right now I suspect engine oil temp will go up, engine coolant temp will go up, and trans temp will stay the same in the 150s. My thoughts

As far as I know you cannot change the shutter temps open or close. You however can remove the 4 middle slats of the shutters without throwing a code. You can also purchase a limiter plate from high performance rams that goes onto the shutter motor that lets you fully delete the shutters with no cel. Like wild one stated you cannot adjust the trans temp in a tune. It’s a mechanical tstat.

 

[Bigskyroadglide]

I removed the four shutters and left the upper and lower I made certain to put it back correctly I snapped the ittle limiter in and reinstalled the shutters it set a code.

I'm perfectly willing to try it again once I get back home but it's set the code within 5 mi after I did that. So I reinstalled them and cleared the code and it hasn't come back