Raptor, I thought there weren't and aftermarket underpulleys for the dakota? Do you know something I don't?
Dakotaho, you have 2wd right?

 

trucky, i asked him and that is what hemifever posted back to me. i don't know but i will be looking into it. do you know where to get an efan from?

 

I got mine half off from Ebay... the black magic 180 with all the trimmings, lucky find. Eric and a few others know where to get some cheaper ones though that do the same thing, ie: taurus fan

 

Here is how I responded to rick via PM and thought I would post it here and let you guys chime in if you have any other ideas.

My 05 Dak currently has 3.55 gear ratio, 2wd so only one set of gears.I’m planning on towing a 2000lb enclosed trailer with 1700 lbs of motorcycles plus maybe 500lbs of assorted junk in the trailer. My truck is probably 4200lbs, 2 people will be about 310lbs and maybe another 300lbs of fuel and junk. That comes to about:
4200lb trailer + 4810lb truck = 9010lbs.


One advantage you will have is less wind resistance than I do with my travel trailer. THIS IS A HUGE ADVANTAGE. The 4.7 has more than enough power to pull the weight under most conditions but at 45MPH and faster my travel trailer is one big BARN DOOR.


We’re planning a trip into the mountains of Colorado this summer but most of the towing will be more flat.
I don’t drive muchnow. I’ve had the truck for 5 years and have about 33,000 miles on it.
I was interested in your fuel mileage estimates with your 4.10 gear ratio. I had expected to not lose much mileage with the 3.92 gears but it you are getting good mileage with the 4.10s, I would rather go that way.



My recommendation if you choose to do the 4.10 gear swap is to go with OEM vs Aftermarket gears. The Ram 1500 has the same 9.25 differential as the Dakota and the part # for 4.10 ring and pinion is 5015371AD, cost $687 at the dealer. I tried the aftermarket route which was cheaper but after two tries the installer couldn’t get the whine out of them. I checked with both suppliers (Genuine Gear and Yukon) and both of their tech guys admitted that their gears whine. So I ended up having a dealer install the OEM gears and it still took them 2 tries to get them quiet.


If you decide to go with the 3.92 gears; a better idea for the swap is to find an entire rear axle/differential assembly from a late model low mileage salvage vehicle. Believe me…Ring and Pinion experts have a tough time setting up the Dodge/Chrysler 9.25 differential.


That’s what I would have done if the Dakotas came from the factory with 4.10’s. Since the 3.92’s are common you should be able to get the swap out done with parts and labor for under $700 and have a better assurance that it is set up right.


Now, If you are planning only one trip with towing a small amount in the hills; a less expensive way to get from 3.55 to 3.92 (actually 3.88) is to find some low profile tires that are 2.6” shorter in diameter than your current tires. No need to worry about matching the weight rating of your OEM tires since the tongue weight of your cargo trailer is going to be far less than a travel trailer. Then sell the tires on craiglist when your trip is over.



I did that as a test before spending the $$$ on the gear swap. I used the following tires: Yokahama Avid 235/65/16 which are 2.6” shorter than OEM. The Kumho 255/60/16 is another that’s 2.6” shorter.



Just be sure that you either change all 4 tires or carry an extra spare tire/wheel with the same dimensions as the low profiles in the event you have a flat on the rear. Running tires on the rear with 2” difference in height for any appreciable distance will seriously damage the spider gears and possibly more.


Another thing– Am I to understand that the speedo pickup is at the rear wheels so thatchanging the gear ratio does not require any recalibration ?


No. On the 05 Dakota the speedo pickup is on the tranny. From a 3.55 to 3.92 the speedo will read 6MPH faster than actual. From 3.55 to 4.10 it will read 9MPH faster than actual. The fix for this is going to cost a minimum of $200 for either a speedo gear change out or a Superchips electronic Speedometer tuner. For another $100 bucks you get the full Flashpaq which will add significantly to the performance as well as correct the speedo reading.

Bottom Line: If I were you, I would try the low profile tires and a Superchips Flashpaq or Cortex to get the best value per $$$ spent. Max loss on 4 tires after re-selling them $200. Superchips Tuner about $325 and they re-sell for at least $200 on ebay. One more plug for Superchips. I can also use it on my ’09 Ram. So if you end up buying another Dakota or Ram it can be reprogrammed for the new vehicle.

 

Trucky, Air Ram has a 25% underdrive pulley for the 4.7. It comes with a different harmonic balancer that is supposed to help smooth out the engine and let you rev higher safely (or something like that).

All this talk is making me excited to order mine. With the 3.92 gears running 32" tires, it pulls well up to 100mph. I just want to see how much faster I can get there now

 

I still can't figure out how to get gears for a 4x4, no one supplies them, and I just got huge rims. Wo is Travis.
Thanks for the underdrive pulley find!
Dakotaho, good info, but...my eyes hurt lol.

 

Let me know how it works for you. Man I wish I had your motor. Even in the '08 and later Ram, the 4.7 owners rave about their performance.

 

I don't think I'll be able to shut up about it once I get it

 

i know SC are pretty much universal correct? because im looking on ebay and alot of ppl on there have the Cortex with a certain truck,car, or models. ive never bought one but i have the money for one and looking jsut not sure if i should save it for the shocks i need... lol im looking at this one atm

http://cgi.ebay.com/ebaymotors/Super...Q5fAccessories

 

NO, not universal. Cortex and Flashpaq are both vehicle specific. Also, on a used tuner, Superchips may charge you to do a setup for your vehicle.

Here's the Superchip forum link: A little research there might clarify it for you.

https://www.superchips.com/forum/index.php