2011+ Ram and other RFE owners delete ATF heater

[ofelas]

Unfortunately, I haven't watched the videos, hands been busy & soaked in ATF all day ;-)

I build a couple RFEs every month, along with various REs & RHs, all behind Cummins, was merely curious as to where the fluid temp sender was in your particular truck.

"This Horse-S*** probably flies on a Ram Forum where cliques decide what's best everyone? "

Not sure about the above sentence in italics - certainly sounded like a personal attack against someone posting about their hobby; I could say the same about certain members here, where I've seen plenty oat manure with obsessing about oil weights - when all one has to do is look at the oil filler cap, but I guess I'll put that down to thin vs thick cliques ;-)

At the end of the day, I browse, learn, and really only place value on a few members' posts, and the rest is garbage in, garbage out.

 

[burla]

Hey man, sounds like you got a [censored] of a hobby, and probably some real good info in your brain. You work at a transmsion shop? Hopefully you wont mind, but I'd like to use you as a resource sometimes? We are as a group over there doing a lot of research with the rfe transmsions lately, maybe I can pick your brain from time to time? Most of us are happy we ended up with the rfe's, as seas like the 8 speeds are getting thier fair share of problems, not that the rfe is a "good" transmsion, lol.

 

[kstanf150]

Burla I get what you mean sir

Question for ya in your line of work what's norm operating
temp for a Ford 6 speed in a 2018 F250 gas burner
According to the dash read out display 197-200 range seems
common.
Thanks

 

[burla]

ofelas did you get that? ^^ Sounds normal.

Second question, I use tow haul mode all the time for the extra line pressure, but I wonder if the valve body can handle that long term. I've actually been doing for seven years, but I wonder if I should get a gasket or valve body plate to handle it long term. ofelas also what do you think about the rfe solenoid? Are they a failure point? Some guys are modding them with the GM solenoid somehow, worth while?

 

[clinebarger]

Originally Posted by ofelas

"This Horse-S*** probably flies on a Ram Forum where cliques decide what's best everyone? "

Not sure about the above sentence in italics - certainly sounded like a personal attack against someone posting about their hobby


It wasn't mean't to be a personal attack.

 

[ofelas]

Depends on how much HP you're making at the wheels.

A good place to start would be to check the CVI values with EZLynk or AlfaOBD.

If you decide to rebuild your transmission, a torque converter stalled to what you want your truck to do, modifying the pump & input drum with a few extra clutches would work well along with some valve body tweaks (don't cheap out on the valve body, get a custom one tailored to your truck's intended usage).

If aiming for up to 700HP or so, you can go with a better flex plate, input shaft & a larger input drum.

As far as solenoids - nothing wrong with an OEM solenoid as long as you upgrade the solenoid switch valve & use a spacer block to correct flexing issues.

Above that HP level - well, go with a stout rebuild on a 48RE.

Temp wise - I aim for pan temps about 10F less than coolant temps.

A better explanation about fluid sender locations here - https://goerend.com/transmission-fluid-info/



Originally Posted by burla
ofelas did you get that? ^^ Sounds normal.

Second question, I use tow haul mode all the time for the extra line pressure, but I wonder if the valve body can handle that long term. I've actually been doing for seven years, but I wonder if I should get a gasket or valve body plate to handle it long term. ofelas also what do you think about the rfe solenoid? Are they a failure point? Some guys are modding them with the GM solenoid somehow, worth while?

 

[burla]

thanks man, great info.

 

[meep]

The critical knowledge here is to know this part may have a predictable lifespan and to change it out before it tanks. If it were mine, I'd want to replace the valve either with OEM or aftermarket. To me, keeping the trans in its desired op temp has its benefits.

 

[DoubleWasp]

Bulk oil temperature is only a part of the equation. Converter Outlet Temperature can be WAY above bulk temps. One of the Chrysler transmission engineers reported COTs of nearly 400°F on the proving grounds, with a negligible change in bulk oil temps.

If COT exceeds 300°F, it's time to downshift or slow down.

I do a lot of towing, so I keep my trans as cool as possible. I have a sensor immediately after the converter (trans cooler out line, before cooler). Temps of nearly 300 are not uncommon with the Converter unlocked.

That is how fluid ends up oxidized even though bulk temps paint a Rosy picture.

 

[-SyN-]

Thanks Burla - DoubleWasp - ofelas: For your posts!

I own a 2017 Ram 6.7L CTD w/68RFE & I due to reading about many of these thermal valve blocks failing and causing transmission overheating and some type of internal damage. I chose to remove this Thermal Block and install a delete block which now ATF is constantly flowing from the 68RFE to the Cooler up front.

Being that the ambient temps are still from 30-50*F my temps dropped from an average 165-168*F not towing to 125-135*F not towing.
It will be interesting to see where these temps end up during the summer months when the temps reach 95-110*F.

I mainly did this due to in a yr or 2 we have plans on purchasing a new 5th wheel RV. (Toy Hauler)
I'm betting she will be at least 15K lbs. I prefer to have my ATF temps as low as I can during this period. (Just Me)!
I do still have plans on installing a PML transmission pan w/Drain Plug for easy servicing in the future.

So far at those lower temps the 68RFE reacts/shifts perfectly fine. No issues what so ever.

 

[burla]

Yeah, great plan there for 5th wheel towing. Take all of the CAFE tech you can out of that baby. Guess you are stuxk with DEF. Glad you avoided the mechanically heated diffs, transmsision and mds of the 1500's.

 

[DoubleWasp]

My Ram has no cooler block, thankfully. If it did have one, I would get rid of it.

 

[CC1981]

Since when has higher trans fluid temps been good for the transmission? I'll keep my truck the way it is: without the TBV. 51k of trouble free miles with my 65RFE and 6k of that was towing my 4000lb camper across the country and back. All while running between 135-150*. I saw 175 once while going up the Ike. Redline C+ is in it as well.

 

[BrianF]

In my current 3500 with the AS69RC, it has the TBV. Unloaded cruising down the highway it hits between the 50 to 60 C mark. Towing heavy and I have not seen it crest 75C.

I cant recall what the 545RFE in my old 2011 sat at but I did once get it up to the 107 C mark when pushing a heavy headwind with max load and trying to maintain some speed.

 

[02SE]

Originally Posted by BrianF
In my current 3500 with the AS69RC, it has the TBV. Unloaded cruising down the highway it hits between the 50 to 60 C mark. Towing heavy and I have not seen it crest 75C.

I cant recall what the 545RFE in my old 2011 sat at but I did once get it up to the 107 C mark when pushing a heavy headwind with max load and trying to maintain some speed.


In my Dually with the AS69RC and the TBV, the highest trans temp I've seen as reported on the gauge cluster is 178° F, or approx. 81° C. That was towing a 5th wheel toy hauler that weighs 26.5K lbs loaded, up a 10% grade for about 5 miles with ambient temps running 103° F. The A/C was running the entire time, with no signs of distress from the truck. Just about all this truck does is tow the toy hauler. The fluid still looks new.

 

[supton]

My truck with no towing whatsoever on a highway run will have convertor outlet at 195F, or basically engine coolant temp (no surprise, there is a coolant to ATF heat exchanger). That is convertor locked and miles and miles of easy driving. I've seen 230F on mild towing with unlocked convertor. I've given up caring as I know the transmission doesn't care (Aisin). I do wonder what it'd be like if I ever actually used it at its indicated towing limits...

 

[BrianF]

I will give the Aisin a nod for its abilities. It never breaks a sweat. We paid a premium for it but I wouldn't have it any other way.