CrazyScotsman
Well-known member
Jon. What ya trying to do ?, Trying to be BIGFOOT pulling a Big Horn
trdeal
Past North Carolina Chapter Leader
What is your gear ratio now?I am towing our Landmark with the 6.0 and 4.10 gear ratio and it does fine.Good on take off and just going down the road.Is anyone towing with 4.30 gears? I am thinking about changing to this setup. I am running 33in tires. Just wondering if anyone has experience with this combination. Thanks JON
jnbhobe
Well-known member
Gears are presently 3.73 but with the tire change from 265-70-17 ( 31.6 in ) to 275-70-18 ( 33.2 in ) it comes out to about 3.55 now. I'm going to change ratios, but don't know weather I want 4.10 or 4.30 . Hoping to get some different peoples opinions. Thanks JON PS I only use this truck for towing,
PS I only use this truck for towing,
jmgratz
Original Owners Club Member
Is anyone towing with 4.30 gears? I am thinking about changing to this setup. I am running 33in tires. Just wondering if anyone has experience with this combination. Thanks JON
There may be some confusion here. You say you are running 33 inch tires...are you aware a 33 inch tire is a tire larger than which is used on an 18 wheeler? I think you mean you are running 18 inch tires ... your tire size is the 18 inch according to your 2nd post. quote - Gears are presently 3.73 but with the tire change from 265-70-17 ( 31.6 in ) to 275-70-18 ( 33.2 in ) it comes out to about 3.55 now. I'm going to change ratios, but don't know weather I want 4.10 or 4.30. end quote Remember the tire size is the inside diameter not the outside diameter.
truknutt
Committed Member
Not always true, some manufacturers still use what I refer to as the old Bias tire numbering system (I know that's not the actual terminology).
This is from the Mickey Thompson Tire web site as an example:
Baja ATZ Radial Plus 33X12.50R17LT OWL
Section width: 12.5
Tread width: 9.6
Overall Diameter: 32.5
Tread depth (32nds): 17
jnbhobe
Well-known member
Jim; Yes there is some confusion, you are talking about wheel diameter. I am talking about tire diameter witch is what you need to figure gear ratio.tire diameter is a combination of wheel diameter, percentage of aspect ratio and section width. (http://www.dirtroad.com/gears.htm) Here is a link to some of the calculators.I am looking for some member input of someone with 4.10 gears and a F-350 tow boss with 4.30 gears. Thanks, JON
Tom of Ypsi
Well-known member
I have the 4:30 rear with 19.5 tires on my 6.4 F-450. Tows great mileage could be better 10-11.3 mpg depending on terrain.
JWalker
Northeast Region Director-Retired
John
I'm also running 33" tires (33x12.12.50R17) on my 6.0 Ford. I'm curious, If a 33" tire changes the ratio from 3:73 to a 3:55. What does it change a 4:10 to? Or a 4:30 to? Is this a considerable difference? What is the cost of changing this over? Is it more cost effective to switch back to the oringinal tire size?
Thanks for the info.
I'm also running 33" tires (33x12.12.50R17) on my 6.0 Ford. I'm curious, If a 33" tire changes the ratio from 3:73 to a 3:55. What does it change a 4:10 to? Or a 4:30 to? Is this a considerable difference? What is the cost of changing this over? Is it more cost effective to switch back to the oringinal tire size?
Thanks for the info.
dieselengineer
Charter Member
Jon
You could go with a underdrive unit and have the best of both worlds.
You could go with a underdrive unit and have the best of both worlds.
jnbhobe
Well-known member
Jamie; stock tires are 265-70-17 and 31.6 in tall. My tires are 275-70-18 and 33.2 in tall. 4.10 gears would be a 3.90 ratio and 4.30 gears would be a 4.09 ratio hope that helps you out. I ordered my stuff today. My Ford dealer is going to do it for me, that way we can still keep it under the factory warrenty. JON
westxsrt10
Perfict Senior Member
Jamie; stock tires are 265-70-17 and 31.6 in tall. My tires are 275-70-18 and 33.2 in tall. 4.10 gears would be a 3.90 ratio and 4.30 gears would be a 4.09 ratio hope that helps you out. I ordered my stuff today. My Ford dealer is going to do it for me, that way we can still keep it under the factory warrenty. JON
Are you going with the 4:10s?
westxsrt10
Perfict Senior Member
Wesrxsrt10; No I am going with the 4.30 gears. That is the optional gear for the V-10 and the standard gear for the F-350 Tow Boss. there is only 3 mph difference at 2000 rpms. 67.7 vs 64.3. JON
Looks like Ford is forcing higher gears (3.55s) on the new diesel trucks ...http://www.ford-trucks.com/forums/882789-3-55s-only-wtf.html
I pull 10K max. and the 4.10s with stock 34" tires does just ok, 4.30s would have been perfict.
jnbhobe
Well-known member
OK, here's the update. The gears were changed by my local Ford dealer,just under $2 G's. Changed both axels, to 4.30 ratio. Have not towed the rig yet. We made a solo run thru eastern Ohio today, a little over 300 miles,averaged 15.3 mpg. Fuel tanks were full and I had 24 aluminum wheels in the bed. I only lost about 3/4 mpg. 200 rpm per 5mph,2200rpm @ 70mph, 2000 @ 65, 1800 @ 60 and 1600 @ 55. I can't wait to try it with the trailer, maybe on saturday.If not its off to Branson next friday. JON
2010augusta
Well-known member
I just found out yesterday that our 450 has the 4:30 gears, and we have the 6.0 PSD, so our mileage is about 9.0, but it pulls the trailer great.
jnbhobe
Well-known member
Well I got to pull the 5er today. Did a 15 mile run across I-90 I'm happy runs along at 65mph in OD on cruise control. Shifts out of OD on the hills still maintains 65mph.Glad I went with the 4.30 gears, we'll give the real test next week going to Branson. YEE-HAA another Rally. Jon
Grdsman
Member
Well I got to pull the 5er today. Did a 15 mile run across I-90 I'm happy runs along at 65mph in OD on cruise control. Shifts out of OD on the hills still maintains 65mph.Glad I went with the 4.30 gears, we'll give the real test next week going to Branson. YEE-HAA another Rally. Jon
I realize this is a bit old, but I haven't really heard definitively if the 4.30s were a good move or not. I have an '05 F-250 with the 6.0 and the same tire setup (2008 f350 wheels and tires) and am thinking about moving from 3.73 gears to 4.30s. My truck seems like a bit of a dog going up some of the passes that I see other trucks hauling up just fine. I saw an older F-350 pulling a bigger toy hauler up Trout Creek Pass this weekend at a speed that I knew I couldn't go up it at.
codycarver
Founding Wyoming Chapter Leader-retired
I have the 4:30 gears in my new ford and so far have no complaints. We travel a lot of hilly country (2-3% grades) around here and it hardly ever comes out of 6th gear. We were over in the black hills and Big Horn mountains this weekend and pulled the 7% grades in 4th @ 50-55 mph. I'm not sure what Ford is calling it's down hill braking system but whatever it is I like it. Hardly had to use the brakes going down the steep grades and according to the computer we are averaging 11.5 MPG although I have not confirmed that the old fashioned way.
