[BPonRTE66]

Hi. I have a 2008 Dodge Ram 1500 quad cab truck with the gas eating Hemi. I love the truck but it seems like I stop at every gas station to keep gas in it. It’s got 50,000 miles on, yes 50K. It has the stock 3 speed trans. The trucks these days are sporting a 6 speed trans and are getting a lot better gas mileage. So instead of buying a new truck to get better gas mileage I was looking at changing the trans to a 6 speed. Does any one know if it could be done and whereabouts would I go to get it done.

 

[1979Malibu]

There isn't much you can do to help that truck get better fuel mileage. You should have the 5 speed automatic from the factory. That already has 2 overdrive gears. I'm not sure the 6 speed would really help enough to justify the cost in getting it swapped.

 

[BPonRTE66]

There isn't much you can do to help that truck get better fuel mileage. You should have the 5 speed automatic from the factory. That already has 2 overdrive gears. I'm not sure the 6 speed would really help enough to justify the cost in getting it swapped.

I’m not much of a transmission guy but when going forward it only shifts into 3 gears and then 1 in reverse. That’s why I thought a 6 speed might be better to get the rpm’s down when in high gear

 

[BPonRTE66]

I’m not much of a transmission guy but when going forward it only shifts into 3 gears and then 1 in reverse. That’s why I thought a 6 speed might be better to get the rpm’s down when in high gear

Thanks 1979Malibu. What you posted makes sense. I’ll stop thinking about it

 

[Crosley]

I’m not much of a transmission guy but when going forward it only shifts into 3 gears and then 1 in reverse. That’s why I thought a 6 speed might be better to get the rpm’s down when in high gear

Automatic trans in that truck should be a 545RFE , which is a 5 speed trans. If you feel 3 shifts, that is at least 4 gears: 1-2 , 2-3 , 3-4 ... The trans may skip shift a gear, that shift strategy is more common in the 8 - 10 speed automatics.

If the trans really is only using 3 speeds, then there is a malfunction. It may not be using the over drive gears and that will affect MPG

 

[BPonRTE66]

Got it. Thanks.

 

[BogiesAnnex1]

We rented a Toyota Tundra last summer for a big hauling job over the mountains. It was equipped with a turbo V6 and 10 speed automatic. I found the fuel mileage poor and the transmission busy to the point of annoyance in the mountains. It seemed much more settled in city driving but around here there isn’t much flat driving so if you live in flat to rolling hills these type transmissions may prove to offer the improvements they lay claim to.

I rather think these 6,8,10 speed transmissions and you can probably dump CVT’s on this pile are just game players to point answer getting good numbers out of government emission and mileage standards, and I don’t just mean US standards as these rules are pretty universal across the planet. So I think these many speed and continuously variable transmissions are more for gaming the legal system in the laboratory than providing any actual performance improvement in the real world.

Add to headaches these days transmissions are shift controlled by a computer, changing to a transmission with more gear selections would not match the programming of your truck. You can add to that a security problem where each major component of modern vehicles is serialized to the computer of the vehicle so you just can’t replace things with junkyard parts without getting in to correcting this.

A lot of effort and cost with minimal result in my view.

Bogie

 

[BPonRTE66]

Explained very well. I’ve made my choice. I’ll keep what I’ve got. Thanks.

 

[BPonRTE66]

Automatic trans in that truck should be a 545RFE , which is a 5 speed trans. If you feel 3 shifts, that is at least 4 gears: 1-2 , 2-3 , 3-4 ... The trans may skip shift a gear, that shift strategy is more common in the 8 - 10 speed automatics.

If the trans really is only using 3 speeds, then there is a malfunction. It may not be using the over drive gears and that will affect MPG

After rereading your answer. I do believe it shifts as you mentioned…… so it is a 5 speed. 4 going forward and the reverse. Makes total sense to me. Thanks

 

[matt167]

My fiancé gets 16-17 mpg in her 2015 with 5.7L hemi that has AFM and the 9 speed trans. If you are getting within a few mpg of that, I would just run with it

 

[joe_padavano]

After rereading your answer. I do believe it shifts as you mentioned…… so it is a 5 speed. 4 going forward and the reverse. Makes total sense to me. Thanks

"Five speed trans" means five FORWARD gears plus reverse.

 

[BPonRTE66]

My fiancé gets 16-17 mpg in her 2015 with 5.7L hemi that has AFM and the 9 speed trans. If you are getting within a few mpg of that, I would just run with it

Ya. I’m going to stay with the trans I have. I got a lot of good info from everyone on this forum, this explanation helps to seal it, very good comparison. Thanks.

"Five speed trans" means five FORWARD gears plus reverse.

then I have a 4 speed trans.

 

[U_Boat]

Think of getting a programmer (Banks?) to "de-smog" the factory tune, especially for light load driving. Transmission swaps are not a trivial task.