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2023 ram 6.4 not shifting into 8th untill i hit 70 mph

Baird ram

Baird ram

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MMy truck will not shift in the eighth year until I hit 70 miles per hour on flat.Roads are even going downhills on the interstate.Is there something wrong
 
Punctuation.

What axle ratio? How many miles on the truck? 70 seems excessive.


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I have the 4.10 rearend and 285/60/R20. Shifts into 8th at 65.

Keep in mind both 7th and 8th are overdrives.
 

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It's under warranty and I took it to the garage , and they said they couldn't find anything wrong , but it will ride in seventh gear at 68 forever
 
Have you installed larger tires?

My 2020 shifts into 8th at less 55 and will hold it down into the 40s.

D

Post in thread '2025 8 speed'

dngrabs said:
Can anybody with a ‘25 6.4 and 8 speed tell me when their HD shifts into 8th? I’ll be running 60+ mph and 2000+ rpm and this thing doesn’t even think about upshifting. I don’t have many miles on it, so will it get better? Doesn’t make sense to be spinning the engine that fast with another gear to use.

I’m not towing anything and it’s not in tow/haul mode.
Click to expand...
My 2020 6.4 with 4.10 gears shifts into 8th at 53 mph and will hold 8th down to 46 mph.

 
Nicely optioned truck. Curious to know if the tires have been swapped out for something taller.

I want to say my 3.73 truck will be in 8th with MDS kicking in around 52 on flat ground. I also don’t pay much attention even with active gear on the display. Now I will

With 80k it could use a trans fluid change. May help.


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I have a 2026 2500 with the 6.4 on a 3.73 axle. (It's brand new). I've noticed the same characteristic, it doesn't like to go into 8th until I get close to 70 mph. I don't think there's anything wrong tho. Speed limits out west on the interstate system are often 80 mph. If you live east of the Mississippi, you don't get to drive that fast, legally at least. Another observation is that it likes to stay in 8th gear once it goes into it, even down into the 50-60 mph range. Also, I don't hear a lot of difference between 7th and 8th gears. I wouldn't worry about it.
 
I have had no real issues even after 37” tires which linger in sixth and seventh gear longer. I guess that also just depends on how I’m driving the truck.
 
dieselscout80 said:
Have you installed larger tires?

My 2020 shifts into 8th at less 55 and will hold it down into the 40s.

D

Post in thread '2025 8 speed'

dngrabs said:
Can anybody with a ‘25 6.4 and 8 speed tell me when their HD shifts into 8th? I’ll be running 60+ mph and 2000+ rpm and this thing doesn’t even think about upshifting. I don’t have many miles on it, so will it get better? Doesn’t make sense to be spinning the engine that fast with another gear to use.

I’m not towing anything and it’s not in tow/haul mode.
Click to expand...
My 2020 6.4 with 4.10 gears shifts into 8th at 53 mph and will hold 8th down to 46 mph.

Click to expand...
No stock 275/70/r18
 
Baird ram said:
No stock 275/70/r18
Click to expand...

The window sticker you posted says night edition 20’s. No?

Regardless, they shouldn’t affect the shifting unless substantially larger in size.


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Yes I know I asked they said the guy didn't order them wish he did it's a used truck going to bet black ones soon
 
There was another guy said his dose it too so a couple of guys said ut was normal. But man 2200 rpm at 68 seems another. Thank for the info
 
My 2024 6.4L with 3.73s shifts into 8 on flat roads around 63 - 65 MPH when I'm not towing a load.

It takes forever, if it ever does, to shift into 8th on hilly roads and when I'm towing.
 
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