over rev-ing

[rravary]

When driving under load (towing, load in bed, going up hill) my truck will over rev to 5k-6k RPM. It will occur when the RPM's rise up to close to 3K RPMs as the load on the engine increases. The engine will over rev to very high RPMs. not sure if this is a TCM issue. The transmission was replaced by the previous owner. Anyone have an idea on the cause?

 

[Wild one]

When driving under load (towing, load in bed, going up hill) my truck will over rev to 5k-6k RPM. It will occur when the RPM's rise up to close to 3K RPMs as the load on the engine increases. The engine will over rev to very high RPMs. not sure if this is a TCM issue. The transmission was replaced by the previous owner. Anyone have an idea on the cause?

That's not really over revving,the trucks are set to shift at 5600 rpm from the factory.Mine is tuned and it shifts at 6600 rpm,and isn't over revving,there's guys that run an even bigger cam then i do and have their trucks set up to shift at 7000 rpm.The engines only 345 cubes,so it's relatively small with a short stroke,and it'll handle rpm pretty well. Remember the old 275 horse 340's,they loved rpm,the 5.7 isn't really any bigger,and it likes to rev to.

 

[Nick@GotExhaust]

Are you saying it will be at 3k then all of a sudden rev straight to 5-6k? If so that sounds like a torque converter issue. I would have that checked out, as that will only get worse if not taken care of. If you can open the fill hole on the trans and see if you can get some fluid on the tip of your finger(while wearing gloves) and see if it looks or smells burnt.

 

[Wild one]

Are you saying it will be at 3k then all of a sudden rev straight to 5-6k? If so that sounds like a torque converter issue. I would have that checked out, as that will only get worse if not taken care of. If you can open the fill hole on the trans and see if you can get some fluid on the tip of your finger(while wearing gloves) and see if it looks or smells burnt.

He's got a 12 Nick,so he should still have an RFE transmission with a dipstick.

 

[62Blazer]

Need some more details. When it revs up does it feel like it's still pulling? In that case it just sounds like the transmission is downshifting like you would expect when hauling a load uphill keeping the gas pedal pressed (doesn't have to be to the floor either).
Or are you saying it revs up and feels like it goes to neutral, so you lose power? That's a completely different story and would indicate some sort of issue.

 

[Nick@GotExhaust]

He's got a 12 Nick,so he should still have an RFE transmission with a dipstick.

Ah yes good catch, I forgot about those having a dipstick. Even easier then to do a quick look at the fluid and to check for it being full

 

[rravary]

Thank you every one. My truck has the sealed transmission with NO dipstick. When it over revs it can go up around 8k RPMs. The truck acts like it went into neutral when it does this--no power (torque?). Everything is stock on the truck--no engine tweeks/upgrades.

 

[Wild one]

Thank you every one. My truck has the sealed transmission with NO dipstick. When it over revs it can go up around 8k RPMs. The truck acts like it went into neutral when it does this--no power (torque?). Everything is stock on the truck--no engine tweeks/upgrades.

If your truck is a stock 2012 truck,you have a transmission dipstick,they didn't start using the 8 speed transmission till midyear on the 2013's,and only certain trim level trucks could be had with the 8 speed. Post a picture of your shifter,if you have a column mounted or console shifter,you have the RFE transmission,and it has a dipstick.The only way you could have the sealed 8 speed transmission is if the truck listed in your avatar is wrong,as you have a 2012 listed,with the 6.1,which was never available in any Ram. BTW the 8 speed isn't sealed,it's fully servicable. No way in hell will the truck go to 8,000 rpm,as it's factory limited to 5600 rpm if it's stock.The computor will shut it down at 5600 rpm . Even if you have the truck in neutral and floor it,it'll only go to 4,000 rpm.
I'm starting to really wonder if this is a troll post,as not much of what you're saying will actually happen

 

[crackerjack1957]

If your truck is a stock 2012 truck,you have a transmission dipstick,they didn't start using the 8 speed transmission till midyear on the 2013's,and only certain trim level trucks could be had with the 8 speed. Post a picture of your shifter,if you have a column mounted or console shifter,you have the RFE transmission,and it has a dipstick.The only way you could have the sealed 8 speed transmission is if the truck listed in your avatar is wrong,as you have a 2012 listed,with the 6.1,which was never available in any Ram. BTW the 8 speed isn't sealed,it's fully servicable. No way in hell will the truck go to 8,000 rpm,as it's factory limited to 5600 rpm if it's stock.The computor will shut it down at 5600 rpm . Even if you have the truck in neutral and floor it,it'll only go to 4,000 rpm.
I'm starting to really wonder if this is a troll post,as not much of what you're saying will actually happen

Ditto.......LoL

 

[seems fishy]

It seems you my have slippage,and how old is the replaced tranny and where did it come from? Tell us if it was from a reliable reman. Or from a scrapyard.As others said it doesn't match the usual 2012 tranny as ther is no dipstick...

 

[Dusty]

Thank you every one. My truck has the sealed transmission with NO dipstick. When it over revs it can go up around 8k RPMs. The truck acts like it went into neutral when it does this--no power (torque?). Everything is stock on the truck--no engine tweeks/upgrades.

That sounds more like flair, and a bad case at that. It probably feels like its in neutral because it essentially is: it lost power transfer. This could be the result of low transmission fluid, and that would be your diagnostic starting point.

Regards,
Dusty
2019 Ram 1500 Billet Silver Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, 33-gallon fuel tank, 18” wheels. Build Date: 3 June 2018. Now at 152823 miles.

 

[Bob Horowski]

The details of his posts just don't add up. Some of the info is misleading or inaccurate whether intentional or not who knows?

 

[jawzs2]

Well, his post does say the prev owner replaced the trans, maybe he bought the truck from someone that read on here that you can do the 8-speed swap, dropped a 6.1L in as well - then gave up on it - LOL.

As Dusty mentioned, it does sound like flair - How much\what are you towing?