Notices
1999 - 2003 7.3L Power Stroke Diesel  
Sponsored by:
Sponsored by:

Towing with 35s - 4.56 gearing?

 
  #1  
Old 01-04-2008, 11:24 AM
muff47
muff47 is offline
Freshman User
Thread Starter
Join Date: May 2007
Location: N Stone, CT
Posts: 45
muff47 is starting off with a positive reputation.
Towing with 35s - 4.56 gearing?

Alright guys I'm making a big trip at the end of the month and I'm trying to get my truck all squared away so I won't have any problems. Heading from CT to Florida with a 39' 5 wheel. I will be hauling the trailer a dozen times or so this year. When the trailers not on I do a little bit of highway driving but mostly just open roads.

I've pulled the trailer several times before but only with 33" tires.Once everything was going the truck ran great but took a while to get up to speed. I think lower gearing will really help especially with the 35s on. I'm looking at either the 4.30 or 4.56 gears and possibly a locker while its getting done as well (TrueTrac seems to be at a good price). I did some searching and it seems like most people with 35s would go with 4.30 but I think because I tow the 4.56 would be a better option.

I already have a DP tuner, AFE intake, MBRP exhaust, gauges, 6.0l intercooler + tranny cooler, and will be doing the TC mod, getting a BTS VB and an ITP tranny pan. Thanks guys!!!
 
  #2  
Old 01-04-2008, 11:27 AM
Pocket
Pocket is offline
Moderator
Join Date: Jun 2004
Location: Parker, CO
Posts: 9,293
Pocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputationPocket has a superb reputation
4.30's will bring it closer to stock 3.73/stock tire combo feel. 4.56's will make it feel more like 4.10's/stock tire combo. The 4.56's with 35's will tow better, but fuel mileage unloaded will suffer more.
 
  #3  
Old 01-04-2008, 11:57 AM
muff47
muff47 is offline
Freshman User
Thread Starter
Join Date: May 2007
Location: N Stone, CT
Posts: 45
muff47 is starting off with a positive reputation.
Originally Posted by Pocket
4.30's will bring it closer to stock 3.73/stock tire combo feel. 4.56's will make it feel more like 4.10's/stock tire combo. The 4.56's with 35's will tow better, but fuel mileage unloaded will suffer more.
Good to hear, I was thinking along those lines but needed to check. 4.56 is what I'll go with. I need something to slow me down when I'm unloaded on the highway lol.
 
  #4  
Old 01-04-2008, 04:09 PM
DCSpecial's Avatar
DCSpecial
DCSpecial is offline
Post Fiend
Join Date: Dec 2002
Location: IL, USA
Posts: 6,245
DCSpecial has a great reputation on FTE.DCSpecial has a great reputation on FTE.DCSpecial has a great reputation on FTE.DCSpecial has a great reputation on FTE.
Here's a link to a chart I made with different tires and gear ratios that shows rpms at 70mph:

http://www.FTEs diesel forums.com/fo...ead.php?t=2896
 
  #5  
Old 01-04-2008, 06:42 PM
TwelveAlpha
TwelveAlpha is offline
Elder User
Join Date: Sep 2006
Location: Lincoln, NE
Posts: 622
TwelveAlpha is gaining momentum as a positive member of FTE.
Two things I regret. I got 4.56 instead of 4.30s. My trailer isnt that long, but its 11000-14000lbs depending on the day. I got a truetrac instead of a locker. If I had it to do over again, thats about all I'd change. My rpms at 75 are just stupid.
 
  #6  
Old 01-04-2008, 09:45 PM
tumbleweed2's Avatar
tumbleweed2
tumbleweed2 is offline
Senior User
Join Date: Aug 2006
Location: ABQ, NM
Posts: 128
tumbleweed2 is starting off with a positive reputation.
Smile

I installed 4.10's with my 35's. (I incereased tire size by 10 percent over stock and so 10 percent of 3.73's put me at 4.08 (4.10)). It seems to be back to stock. I also have a small 5'er and I hook a boat behind that and I would like to try 4.56 or 4.30 just to see. I may just try 285/75 next set of tires.

Long story short. 4.10's works for me, and milage is about 13mph pulling 3500# . And it pulls 5500# 5er up hills in OD without down shift, especially if I stay above 75mph.

your 39' weighs a lot more though. I bet 4.30 would be a good compromise mileage==power.

Good luck,
 
  #7  
Old 01-04-2008, 10:04 PM
bfife's Avatar
bfife
bfife is offline
still plays with trucks
Join Date: Mar 2004
Location: Twin Falls Idaho
Posts: 1,743
bfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to behold
Two things to consider. with 35's, will your truck bed be too tall to fit under the 5ver and still pull level? Why not consider a US Gear underdrive with a 22% ratio change you can now have the gears to pull when you are hooked to the trailer, and the economy gears when running empty. dollar wise its not that much difference. and having the ability to "splitshift" between gears lets you fine tune your RPM's for your load. I love mine. And it works with manual or automatic trannys. Barney
 
  #8  
Old 01-04-2008, 11:06 PM
PowerstrokeJunkie's Avatar
PowerstrokeJunkie
PowerstrokeJunkie is offline
Post Fiend
Join Date: Jul 2005
Location: 21791
Posts: 14,583
PowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to beholdPowerstrokeJunkie is a splendid one to behold
I do alot of driving under 55ish, and i rarely go over 70 for cruising. I have 35's, and i was considering 4.56's. I drive a 07 with 4.30 and stock tires, and like the RPMs. Its alot quieter though so it will be a little different story in a louder truck.
 
  #9  
Old 01-05-2008, 09:51 AM
muff47
muff47 is offline
Freshman User
Thread Starter
Join Date: May 2007
Location: N Stone, CT
Posts: 45
muff47 is starting off with a positive reputation.
Originally Posted by bfife
Two things to consider. with 35's, will your truck bed be too tall to fit under the 5ver and still pull level? Why not consider a US Gear underdrive with a 22% ratio change you can now have the gears to pull when you are hooked to the trailer, and the economy gears when running empty. dollar wise its not that much difference. and having the ability to "splitshift" between gears lets you fine tune your RPM's for your load. I love mine. And it works with manual or automatic trannys. Barney

I was worried about that at first. I've got a 3.5" lift (only add a leaf in the rear) and with 33s the truck sits almost as high in the back as my buddies stock '06 F350. I've got F350 blocks coming for the rear and with the 35s it'll raise it up another 2-2.5". My hitch is adjustable and can lower it down about 1.5", putting everything pretty close in align. Once I get the 35s in I will load the trailer on and see how she looks.

This underdrive unit is definitely something I'd be interested in getting. I started reading up on both the US gear and Gear Vendor units. The gear vender seems nice because it can shift under full throttle and has a 2 year warrenty. Are there any other units out there? I'd like to do it right the first time but wasn't expecting to spend more than $3k or so on the whole deal.
 
  #10  
Old 01-05-2008, 11:17 AM
bfife's Avatar
bfife
bfife is offline
still plays with trucks
Join Date: Mar 2004
Location: Twin Falls Idaho
Posts: 1,743
bfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to beholdbfife is a splendid one to behold
the GearVendor unit is availible as an overdrive only. Also you cannot use it with an Ebrake, in reverse, in 4 wheel dr or decellerating down steep hills. The US Gear dual range can be ordered as an overdrive or underdrive. it also can be used in any range, drive mode, and with exhaust brakes. I have owned both units and towed heavily with both. the US Gear is by far the better built unit. of course thats JMHO. The GV is a small automatic tranny. you must be at speeds abouve 25 mph in order for the internal pump to work. the US Gear unit is a small manual tranny. as long as you're moving it will shift with just the flip of a switch. As for shifting under full throttle, i found the GV banged so hard that I didn't feel comfortable doing it. The US Gear units requires just a slight lifting of the throttle, The unit should cost around 2500-3000.
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Firefighter615
2004 - 2008 F150
5
03-05-2017 12:56 PM
TSmylie
1999 to 2016 Super Duty
12
08-27-2015 08:05 PM
TSmylie
Conventional (Bumper Pull) Towing; Travel Trailers & Pop-ups
4
08-25-2015 02:22 PM
DSN46
Excursion - King of SUVs
17
10-30-2013 11:11 AM
RobbyMartin
1997 - 2003 F150
25
12-15-2009 09:16 AM


Thread Tools
Search this Thread
Quick Reply: Towing with 35s - 4.56 gearing?


Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.