5-Sp vs 6-Sp

[cmckinney]

What is the main difference between the two transmissions? Is the final drive ratio the same between the two or does the 6-sp improve your MPG at Hwy speeds?

 

[Barry]

The 1st and final gear ratios are the same in both transmissions. The 6 speed just has closer ratios to keep the engine hummin'. It is an absolute dream to drive. For what I do, I would not consider anything else. mi dos pesos

 

[Roger rodbolt]

Originally posted by cmckinney

What is the main difference between the two transmissions? Is the final drive ratio the same between the two or does the 6-sp improve your MPG at Hwy speeds?

Overdrive ratio in the 5 speed is . 75 while overdrive in the 6 speed is . 73 so the six speed does reduce cruising rpm a little. I just converted my '98 to a six speed and with 295/75-16 tires, 2140rpm on my Blue Chip FMS tach gives a consistant 82mph on the Garmin Street Pilot GPS. The OEM speedometers on our Dodges generally register too fast. Fuel mileage has dropped but I changed from a HX40 to a B1 turbo while have the driveshafts cut, so I can't offer any advice regarding fuel consumption.

 

[Hammer]

Here are the ratios maybe this will help explain it better... .

5 speed... .

1st----5. 61

2nd---3. 04

3rd----1. 67

4th----1. 00

5th----. 75

reverse-5. 06

6 speed... .

1st----5. 63

2nd---3. 38

3rd----2. 04

4th----1. 39

5th----1. 00

6th----. 73

reverse-5. 63

As you can see the advantages of the 6spd are in its ability to give the truck and motor more ways to apply the torque and hp especially when towing alot,,It will give you that gear we 5speeders need in the middle when one is not enough and the other is too much,,Also it has a much lower reverse gear that help when backing the heavy loads,,After driving them both my preference is the 6 spd but my 98 is a 12 valver and they were not a option so it will be put in,,Hope this sheds some light for you..... Andy

 

[klenger]

I traded in my 2001. 5 5-speed after 6 months for a 2001. 5 6-speed. If cost me a few grand in depreciation. Enough said?



Even empty, the 5-speed has gaps that I didn't like.

 

[Don M]

If your truck is stock or close to it the 5 speed may be at a disadvantage for guys who tow weight.

If you have a modified power curve the gaps that guys talk about are not even remotely a problem because the added power deals with the gear ratio between 3rd and 4th quite well.

Further, the 5 speed is almost 170lbs lighter than the 6 speed.

The 6 speed has the bell housing attached to the transmission and the 5 speed can drop out independently of its bell housing.



5 speed for me.



Don~

 

[MikeR]

Don is absolutely right about the gear gaps and what power you have. I have had both 5 and 6spds and know it's true.

With a higher powered truck, the 5spd gaps are no longer an issue because the engine winds so much faster. On a 6spd truck, the gears are shorter, and now too short for a higher horsepower rig.



It's one of those "I wish I knew then what I know now". I really wished I had kept my 5spd truck.

 

[Wiredawg]

Go 6 spds!

Fellow Rammers:



I have the 6 spd and use every bit of my gearing pulling my 15K lb 5th wheel. I think the 5 spds would acclerate faster, but that's the only advantage I can see in having a 5 spd. I think if you had two trucks equally BOMB'd, the 6 spd would still tow the heaviest loads.



Just my opinion,



Wiredawg

 

[Okie-Go]

We all have an opinion and mine is the 6spd. That is the only way to get the HO engine. I traded an automatic 98ctd for mine and have not regretted it a bit.