65rfe overheating

[NickSteel]

my 6 speed auto is overheating as of recently, only when it’s idling in park, neutral or drive. i’ve noticed that once the trans hits 180 or so you can put it in park and then drop it back into drive and it’ll cool down around 10 degrees, i don’t have a trans thermo on my truck. hottest it’s gotten is 204, and the trans started to shift incredibly slow and smash into gear. when it’s at highway speed it runs from 140-160 usually without issue. is this normal?

this was taken a few weeks ago on 8/8, i have since hit 100K.

also, sometimes when the truck sits for a bit it sounds like a jet engine when it cranks over, like the clutch fan is sticking. another problem which is sort of unrelated but also related is that the trans shifts badly and the engine hesitates horribly with the A/C on, and doesn’t cool down the trans or engine with the e-fan.


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[NickSteel]

forgot to add, fluid level is normal and bright red


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[Burla]

Bypass the Thermo Valve if it is over heating in nuetral. Got to fix it, that rfe wont last at that temp for long. Why do you say no thermo valve, did you already take it off?

 

[NickSteel]

Bypass the Thermo Valve if it is over heating in nuetral. Got to fix it, that rfe wont last at that temp for long.

where is it? behind the grill? i’m about to go and take off the grill to see if i can find it


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[Burla]

Yes 140 to 160 is normal.

 

[Burla]

where is it? behind the grill? i’m about to go and take off the grill to see if i can find it


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Jeff is the second Post in this thread, check out the dyi video. It might be in a different spot for 1500, dunno.

 

[Burla]

 

[NickSteel]

Jeff is the second Post in this thread, check out the dyi video. It might be in a different spot for 1500, dunno.

I think i just found my issue, the top few rows of fins in my radiator are smashed


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[NickSteel]

also there’s no TBV on my truck, i just looked at the cooler lines coming from the tranny and there’s nothing


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[NickSteel]

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[Burla]

I'm not sure about that. You say the temp is climbing in park and neutral while stopped.

One thing you might consider, the 8 speed operates at a much higher temperature and they use a special fluid with pao base oil. Redline c+ is a pao/ester based fluid option for the rfe. And a valve body upgrade to handle higher psi is another worth while upgrade.

 

[NickSteel]

I'm not sure about that. You say the temp is climbing in park and neutral while stopped. Is there no thermo bypass???

One thing you might consider, the 8 speed operates at a much higher temperature and they use a special fluid with pao base oil. Redline c+ is a pao/ester based fluid option for the rfe. And a valve body upgrade to handle higher psi is another worth while upgrade.

Absolutely no thermal bypass valve from what i saw, i looked in the locations of the 68RFE the the 65RFE from looking online and at the videos. And yes, i’m looking into a VB upgrade as well. I will look into t ye redline c+ right now.


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[Burla]

How long of a drive posted that engine oil temp? Is the engine oil also getting hot? I see the coolant was 206, does it pretty much stay right on 203/4 while on freeway?

 

[NickSteel]

How long of a drive posted that engine oil temp? Is the engine oil also getting hot? I see the coolant was 206, does it pretty much stay right on 203/4 while on freeway?

That drive was around 40-50 minutes, and yes, it stays at 201-206 at most on the freeway. Idling the engine can rise up to 220, same with the oil. The trans (as previously mentioned) stays at 140-160 when doing highway speed and can rise up to 180-190 idling, but once speeding up from a stop all 3 drop to normal, takes a bit for the trans but it gets down there


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[NickSteel]

Late night, right after i hit 100K and put it in park. Notice the engine temp rising, the trans followed suit around 10 mins later


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[NickSteel]

Sorry for the spam, but i mildly think it’s the e-fan dying as last night i was sitting in the truck for around 30 mins with the A/C on and this time instead of other times i actually heard the fan kick on, and the truck didn’t go past 206 on coolant and the trans maxed out heat wise at 165.

Maybe time for the 3.7L V6 fan swap.


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[Burla]

You are right on the limit if a problem, it is just a bit high. I wonder what will happen when winter hits.

I think there is a process to check and set the fan on the radiator, I haven't had to look it up. Another worth while thing to consider.

 

[NickSteel]

You are right on the limit if a problem, it is just a bit high. I wonder what will happen when winter hits.

I think there is a process to check and set the fan on the radiator, I haven't had to look it up. Another worth while thing to consider.

I’m gonna try to search it up then, it’s starting to cool down here so i’m not extremely worried about it yet but i will be buying a new rad-fan and removing the clutch fan if the rad fan turns out to be bad.


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[Burla]

 

[NickSteel]

That explains the trans and engine cooling when i tap the gas then. Time for that new e-fan.


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