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R/T Scat Pack 392 Widebody, Xpel PPF / ceramic coated
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Hi, has anyone come across an issue whilst in automatc mode, under hard acceleration car will reach maximum revs in 4th or 5th gear and refuse to change up to the next gear?

I was in custom mode (which for me is track mode with traction control on) accelerating from 50 mph to about 90mph with the car changing through the gears rapidly as normal when suddenly the rev limiter cut in. I'm not sure what gear I was in but it limited the speed to about 90mph at maximum revs and would not change up. I was not in manual mode, and hadn't touched the paddles at all. What makes this more concerning is that it is the second time it's happened in a month. Any thoughts appreciated. [2020 Challenger R/T Scatpack 392 Widebody 8 speed Auto]
 

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Welcome to Challenger Talk. Please post pictures when you get a chance.

How many miles?

So you never get it to go into 6 -8 when it's having issues?

You could always try it in manual mode and see if you can push it up a gear?

If it was me I would have that back to the dealer as fast and safely as I could get it there.
 

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Find my other post... There is a Paddle Shifter TSB that was issued in the first week of October.

My 2020 RT SP WB has the upshift problem with the right side paddle. (She likes to downshift rather than upshift.)
 

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2020 Dodge Challenger Hellraisin Scat Pack
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Hi, has anyone come across an issue whilst in automatc mode, under hard acceleration car will reach maximum revs in 4th or 5th gear and refuse to change up to the next gear?

I was in custom mode (which for me is track mode with traction control on) accelerating from 50 mph to about 90mph with the car changing through the gears rapidly as normal when suddenly the rev limiter cut in. I'm not sure what gear I was in but it limited the speed to about 90mph at maximum revs and would not change up. I was not in manual mode, and hadn't touched the paddles at all. What makes this more concerning is that it is the second time it's happened in a month. Any thoughts appreciated. [2020 Challenger R/T Scatpack 392 Widebody 8 speed Auto]
Can't find a chart but the car in question may not be able to obtain enough RPMs in the higher gears to trigger an automatic up shift.

Generally a car's max top speed is obtained in a lower gear in which the engine can reach its max RPMs.

For the 2020 R/T max speed in 4th gear is 97mph, 5th gear is 126mph. In 6th gear it "jumps" to 161mph. However I do not believe the car can reach 161mph.

The Scat Pack version is similar but I do not have access to a max speed in each gear chart for this model.

Another possible explanation is the engine speed was limited because of for example detonation. For an enginei to make max power requires it run to near red line. To rev this high the engine must be in top tune. A new engine -- assuming it is broken in -- should be able to reach max RPMs but of course one variable is quality of gasoline. if you fueled the engine with a lower octane grade of gasoline than called for by the owners manual or the gasoline happened to be stale this may have resulted in conditions which caused the engine controller to retard timing and this limited the speed of the vehicle.

Assuming you were not trying to reach a speed in a gear the car cannot obtain, and the engine is capable of revving high enough in 4th gear to reach the shift point, for an automatic to fail to upshift before the engine rev limiter kicks in is not a common problem. Since automatic of course means an up shift should happen automatically when the necessary conditions are present which in this case means the engine RPMs got close (enough) to red line and this didn't happen this suggests there is a serious problem with the automatic/its TCM.

The car is under warranty of course so just take the car in.

A problem is if to reproduce the abnormal behavior requires the car be driven in an illegal manner the tech is not permitted to drive the car in this manner. This limits you to only providing an accurate account of the conditions and behavior.
 

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R/T Scat Pack 392 Widebody, Xpel PPF / ceramic coated
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Discussion Starter #5
Can't find a chart but the car in question may not be able to obtain enough RPMs in the higher gears to trigger an automatic up shift.

Generally a car's max top speed is obtained in a lower gear in which the engine can reach its max RPMs.

For the 2020 R/T max speed in 4th gear is 97mph, 5th gear is 126mph. In 6th gear it "jumps" to 161mph. However I do not believe the car can reach 161mph.

The Scat Pack version is similar but I do not have access to a max speed in each gear chart for this model.

Another possible explanation is the engine speed was limited because of for example detonation. For an enginei to make max power requires it run to near red line. To rev this high the engine must be in top tune. A new engine -- assuming it is broken in -- should be able to reach max RPMs but of course one variable is quality of gasoline. if you fueled the engine with a lower octane grade of gasoline than called for by the owners manual or the gasoline happened to be stale this may have resulted in conditions which caused the engine controller to retard timing and this limited the speed of the vehicle.

Assuming you were not trying to reach a speed in a gear the car cannot obtain, and the engine is capable of revving high enough in 4th gear to reach the shift point, for an automatic to fail to upshift before the engine rev limiter kicks in is not a common problem. Since automatic of course means an up shift should happen automatically when the necessary conditions are present which in this case means the engine RPMs got close (enough) to red line and this didn't happen this suggests there is a serious problem with the automatic/its TCM.

The car is under warranty of course so just take the car in.

A problem is if to reproduce the abnormal behavior requires the car be driven in an illegal manner the tech is not permitted to drive the car in this manner. This limits you to only providing an accurate account of the conditions and behavior.
Hi Rockster, this makes alot of sense, thank you.

We took the car out today on a airfield to see if we could replicate the problem, but it's working normally, changing up from 4th to 5th at 98-100mph at around 6,250/6,500 revs.

So I think it was getting 'stuck' with the rev limiter kicking in earlier than it should at about 5750 rpm as it wouldn't go past 92-93mph.

Fuel is super unleaded -99 octane, mileage is 1100 miles, so it's fairly new but broken in. I will report it to the dealer but there is an overwhelming lack of experience of Dodge vehicles here in the UK. With the added difficulty of replicating the problem, especailly at a speed I rarely ever go, I was hoping it might be an issue that Dodge are already aware of that would assist the dealer.

What could be a serious issue is if it ever does it in a lower gear - imagine overtaking in a split second decision to find you are out on a limb with zero acceleration. Whether as F8HemiRT suggests (thank you F8) I could flick to manual mode and change up manually I don't know, but at the time I was completely thrown and decelerated instead. Plan will be to keep an eye on it for next few months. Thanks Rockster and all of you guys for your constructive comments.

Welcome to Challenger Talk. Please post pictures when you get a chance.

How many miles?

So you never get it to go into 6 -8 when it's having issues?

You could always try it in manual mode and see if you can push it up a gear?

If it was me I would have that back to the dealer as fast and safely as I could get it there.
Thanks - 99.9% of the time car works fine. Next time it happens I'll try to see if I can change up manually, but as you rightly say, it needs to be reported to the dealer.

Find my other post... There is a Paddle Shifter TSB that was issued in the first week of October.

My 2020 RT SP WB has the upshift problem with the right side paddle. (She likes to downshift rather than upshift.)
Thanks, yes I came across this issue when researching my own.
 
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