Sorry late to the party but if you want charts here's ya some

https://www.ford-trucks.com/forums/1...xle-ratio.html

 

Thank you, everyone, for your input. I am now the proud owner of a 2011 f250 lariat. Only had 3875 miles when i pulled of the lot. The only downside is it is 2wd but it was $5k less then a similarly equipped 4wd with 22k miles. I drove it home yesterday. This is the only pic i have. The cap will come off and get repainted to match. Very happy so far. I cant wait to hitch up to something. Intitial impression is that it feels more powerful at any rpm, 1k - redline, then my 5.4 with 4.10s and 93 5 star tune. If i want to regear to the 4.30 i only have 1 axle to worry about but the 3.73 feels strong.

 

I tow a 11000 lbs. trailer all over Illinois, Indiana and Kentucky with a 3.73 and it does a fine job, but I would rather have a 4.30 I can see a need. You guys that lock out 6 gear thinking you’ve turned your truck into a 4.30 I’m not following you, all you’ve done is turned a 6 speed transmission into a five speed. The 4.30 is needed for start up not cruising and it gives you improve pulling through every gear including six gear. Also when I tow, I leave it in drive with all gears in, when it can on at or about 65 mph on flat land six gear will come in and cruise very nice.
I have looked into changing my ring and pinion gear out for a 4.30 at my local Ford dealership and they want $1800 plus tax. But Ford says that any changes from original from the factory could bring warranty issues, whatever that means.
Happy New Year everyone.

 

So is the dealer implying that a " dealer changed ring and pinion will not cover issues"? I have often wondered about that.

At some point when my factory tires are shot I plan to change my wheel an tire package. I would like to run 35's but I am also concerned how the truck will act since it is changing my overall gearing ratio.

If the warranty stayed the same and I could pay the dealer I would have them change out the front and rear ring and pinion...... I have not looked into it but if I went to 35's I would like to go to a steeper gear than 4.30's if they were available. This way with 35's and let's say 4.56's (just a guess) i would have closer to a stock setup with 4.30's

 

No that comes directly from Ford, the dealer wasn't sure how it affected my warranty, I think they like staying out of it. And when you talk to Ford they are very vague they just keep repeating you can't change from stock on anything.

 

Well that sucks!


One would think that a dealer could make changes being that they have factory specs and "trained" techs and keep the warranty.

 

Congrats! You know what's next - a towing report when you get that Tow Hauler hooked up

 

Well, i only towed it for a few miles to test the wd hitch setup after adjusting it to the new truck (the 09 was a 4x4 with 5" rear blocks so it sat much higher). It towed very well. In a couple weeks we are taking a trip to Hershey pa for our anniversary. Its about 375 miles or so and lots of hills so it will be a nice test of the new truck and trailer. So far my only complaint is i greatly miss 4wd. Other then that its a great truck. i upgraded my tuner with new tunes from Mike at 5star with 87 eco, 87 preformance and 93 preformance. I have not tried 93 yet but 87 preformance is alot of fun. Anyway thank you everyone for your input.

 

Good to hear ... I'll look forward to your experiences on the hills!

 

I have a 11 250 cc lb 4x4 3.73 gears I tow a 7k bobcat on a 3300lb trailer no problem. Sure the 410s would be better but I have no complaints.

 

^^This is absolutely correct. The part about turning it into a 5 speed is spot on. I know that works for a lot of folks, but just be aware of it.

My only regret on my truck is not ordering to get 4:30's. When my warranty is up I will weigh very heavily the decision to have the gears swapped. Probably from a specialty shop, not Ford. If they would honor the warranty, I might be willing to pay their inflated prices to have it done, but I guess I'll wait. It tows my trailer fine, but it would be better with 4:30's, and I don't care about the mileage, it's not my daily driver.

 

Another way of thinking about it is rear gears are the last torque multiplier so the deeper the gears the better the multiplier.

Denny

 

But... once operating in a transmission over-drive gear,either 5 or 6, the torque is not magically produce by the 4:30 rear gears...right?

example:
3:73 gears, 5th (1st over drive from transmission) engine operating at 2200 rpm = X torque at wheels

4:30 gears, 6th (2nd over drive from transmission) engine operating at 2200 rpm = X torque at wheels.

in this case X should be equal?

 

The rear end gears are the last torque multiplier so lower gears will give you more mechanical advantage through all the gears.

Simple example you need to torque a bolt to 1000 you use a 10 to 1 multiplier so you only have to exert 100 ft lbs to get that torque. If you go to a 5 to 1 multiplier you would need 200 ft lbs to gain the same same torque.

Denny

 

Thanks in advance for the duplicate discussion in the RV forum.

I see it this way:

If you are using 6th gear vs 5th you are reducing torque by X amount at the drive shaft
and you are gaining torque by having the 4:30.

If you are using 5th gear you have more torque at the drive shaft, but are reducing torque with the 3:73 by X amount.

this is under the assumtion the engine RPM and speed (MPH) are the same. just the part (gearing) between the engine and the wheels are different

I'm not doing a good job of explaing