Tranny overheated

[kfp673]

Hello All,

2018 Ram 2500 6.4L Hemi with 4.10. Heading back from camping today, tow/haul mode on, after a long hill my truck suddenly left "D" and locked itself in 4th gear. I was on the highway doing about 65 so it was not that big of a deal, but I could not make it go back to D, upshift, downshift, nothing. Kept driving 2 miles until the next exit which happened to be mine. Seemed fine until I came to a light in town. It never left 4th. Needless to say it was not pretty trying to start from stop with 10k Lbs trailer in 4th gear. Got it going just to clear the intersection and pulled over where I could. Just as I pulled over a light said "Transmission is too hot". I let it idle for about 5 minutes hoping the trans cooler would cool it. After that 5 minutes the light went off but I was still stuck in 4th. Turned the truck off and re-started and all seemed fine for about 4 miles and then the same thing. I was about 10 miles from home thankfully so I limped home, shutting down and restarting at each light. Almost home the engine light went on. I am in warranty so I'll take it in this week but curious if anyone has seen this issue. Truck pulls the trailer great and never had an issue. It does scream sometimes pulling long hills but never felt like it was struggling. Also strange that when I re-start it shifts fine until it locks in 4th again after 5-10 min. Any thoughts? Thanks!

[dodge_guy]

frankwp wrote:

Grit dog wrote:
Cheap insurance? I totally believe in proper maintenance. From personal vehicles to managing or maintaining fleets.
But there is zero “cheap insurance” by performing maintenance significantly ahead of the required or suggested intervals.
I mean, I’m more likely to buy a used vehicle from someone’s Grampa who changed the oil every 3000 miles. But it only shows anecdotally that he may have cared for the rig overall better. There’s no extra residual value. So hypothetically, “if” one was planning to keep the vehicle for 300k or 500k miles, there “might” be a slight decrease in wear, but at that point, who cares? Because the normally maintained vehicle will statistically last just as long.

Research on the subject I've read shows, for example, that oil additives are present and doing their job well past the manufacturer's recommended interval. There is just no upside to more frequent maintenance other than the piece of mind it may give. To some, that's worth the added cost.

You may want to check with GM and the sludging issue their cars had, and they came out with a flash to shorten the oil life monitor interval. So it's not just those of us that know better, manuf and engineers can learn from us also. This goes for filled for life fluids. So if you think you can go 200k miles on trans fluid go right ahead. Us technicians will gladly replace the neglected trans for you.

[frankwp]

Grit dog wrote:
Cheap insurance? I totally believe in proper maintenance. From personal vehicles to managing or maintaining fleets.
But there is zero “cheap insurance” by performing maintenance significantly ahead of the required or suggested intervals.
I mean, I’m more likely to buy a used vehicle from someone’s Grampa who changed the oil every 3000 miles. But it only shows anecdotally that he may have cared for the rig overall better. There’s no extra residual value. So hypothetically, “if” one was planning to keep the vehicle for 300k or 500k miles, there “might” be a slight decrease in wear, but at that point, who cares? Because the normally maintained vehicle will statistically last just as long.

Research on the subject I've read shows, for example, that oil additives are present and doing their job well past the manufacturer's recommended interval. There is just no upside to more frequent maintenance other than the piece of mind it may give. To some, that's worth the added cost.

[Grit_dog]

Cheap insurance? I totally believe in proper maintenance. From personal vehicles to managing or maintaining fleets.
But there is zero “cheap insurance” by performing maintenance significantly ahead of the required or suggested intervals.
I mean, I’m more likely to buy a used vehicle from someone’s Grampa who changed the oil every 3000 miles. But it only shows anecdotally that he may have cared for the rig overall better. There’s no extra residual value. So hypothetically, “if” one was planning to keep the vehicle for 300k or 500k miles, there “might” be a slight decrease in wear, but at that point, who cares? Because the normally maintained vehicle will statistically last just as long.

[kellem]

rhagfo wrote:

dodge guy wrote:

campigloo wrote:
Also keep in mind the only thing a trans flush flushes is your wallet. Just have a proper fluid and filter change

With regular fluid changes yes, that's all you need. If not that a trans flush will flush near 100% of the fluid out of the trans. When I do it at work I don't use any cleaners or additives. Just the correct fluid. Clean goes in and sold fluid comes out.

I have done full fluid changes in the past on our 1989 F250 460, with C6 trans. The cooler return line just dumped into the pan.
Took a bit of fluid, but once the pan and filter had been removed and replaced, you added enough to fill the pan. Then disconnect the return line with a big catch pan under it, start the engine, while helper ran the trans through the gears, you added fluid while watching the fluid coming out of the return line. When it changes from dark red to bright red stop the engine and reconnect the return line. Check the fluid level and top off.
I don't know if you can do that on current transmissions.

That's precisely the way I've done it for years with wife in vehicle.

NOTE:
You'll know quickly if you've disconnected wrong line apon start up, instant mess.

[rhagfo]

dodge guy wrote:

campigloo wrote:
Also keep in mind the only thing a trans flush flushes is your wallet. Just have a proper fluid and filter change

With regular fluid changes yes, that's all you need. If not that a trans flush will flush near 100% of the fluid out of the trans. When I do it at work I don't use any cleaners or additives. Just the correct fluid. Clean goes in and sold fluid comes out.

I have done full fluid changes in the past on our 1989 F250 460, with C6 trans. The cooler return line just dumped into the pan.
Took a bit of fluid, but once the pan and filter had been removed and replaced, you added enough to fill the pan. Then disconnect the return line with a big catch pan under it, start the engine, while helper ran the trans through the gears, you added fluid while watching the fluid coming out of the return line. When it changes from dark red to bright red stop the engine and reconnect the return line. Check the fluid level and top off.
I don't know if you can do that on current transmissions.

[Grit_dog]

This entire thread makes me wish I kept my 6 speed row yer own truck!
Lol

[afidel]

ACZL wrote:
Tho I have a Ford, I'm w/ dodgeguy on changing tranny oil every 25-30k. Likewise, I still drop oil every 5k as well Like DG said, "Oil is cheaper than........"

On a side note, this thought came to mind as I was reading the updates and suggestions and all. Why can't mfr's design the software to have the engine fan come on (even tho water temp is ok) if a sensor is telling the computer something is getting hot and to draw more air thru to try and cool things down?

Huh, I'm doing oil every 5k and just did the tranny at 45k miles, I'm following the severe duty schedule in the manual. I do watch my temps and even when climbing the Beartooth mountains I've never been in the danger zone on tranny temps. Now you're making me wish I had asked the shop to grab a retain to send off to a lab.

[kellem]

I can tell you from experience that tranny temps should be monitored while towing in the big hills.
175* - 220* is the safe zone.
240* varnish starts to form and higher, seals harden.

Was towing in the mountains in WV and saw 265* on my Chevy avalanche before I could Crest the hill and lost the transmission a week later sitting in the parking lot of Petsmart.

All my trucks get auxiliary coolers now if not already equipped.

[trail-explorer]

deltabravo wrote:

kfp673 wrote:
I have my trailer break gauge

Which trim level trucks have a gauge to show a broken trailer?

I think it's the PlatinumBigHornLaramieDenaliLTZ model

[deltabravo]

kfp673 wrote:
I have my trailer break gauge

Which trim level trucks have a gauge to show a broken trailer?

[dodge_guy]

campigloo wrote:
Also keep in mind the only thing a trans flush flushes is your wallet. Just have a proper fluid and filter change

With regular fluid changes yes, that's all you need. If not that a trans flush will flush near 100% of the fluid out of the trans. When I do it at work I don't use any cleaners or additives. Just the correct fluid. Clean goes in and sold fluid comes out.

[campigloo]

Also keep in mind the only thing a trans flush flushes is your wallet. Just have a proper fluid and filter change

[pitch]

yes

[goducks10]

Thats a lot of variance. So at 40* your trans temp is 120 and at 90* your trans temp is 170?