Bass Fishing Home PageTM



Boating Equip.
Tackle Shops
Fishing Acc.
Fishing Reports
BFHP Articles
Fishing News
Fishing Tactics
Places to Fish
Boat Ramp Stories
Other Topics
Other Fishing Topics
Swap/Sell (no boats)
Props 4 Sale

Boats 4 Sale
Saltwater Fishing
Striped Bass
Lure Making
OBX Wildlife Photos
More Politics

SUBJECT: # 12805: question on rear end 3.73 vs 3.55

Submitted by basskiller2 ( from KENTUCKY on 8/30/2007 11:08:00 AM

I am looking at a new ford truck. a lot of the 2007's that are on the lots have 3.55 gears. looking at a 5.4L v8 engine. fisrt question is what is the difference in driving and towing comparing the 3.73 vs the 3.55. next question is with the 5.4L engine, how much of much of a difference will it make comparing the 3.73 vs the 3.55 rear end. what would you do, find one with the 3.73 or buy the 3.55. i have a 18.5ft stratos boat that is being towed.


  1. 8/30/2007 2:38:00 PM Submitted by JohnM from TN says IMHO the 3.55 with the 5.4 will do fine with a 18 foot bass boat
    That being said I always look for and buy at least the 3.73's just because I like the go power when I want it but that is strictly a personal thing not a "need". Example, I am dragging around a 18'7" Champion with a 5.6L Nissan with their 4.10 equivalent rear end LOL. WAY overkill but I am not worried about using the truck to haul a tractor, big trailer, or most anything else I want to up to it's way over rated capacity. I get about 2 MPG less on the interstate than a truck without that low of rear end. If my truck got the window sticker of 18 and I am getting 15 and I drive half the 15K a year average on the interstate I pay about 250.00 more a year at 3.00 a gallon. I figure if I cannot afford the 250 to 300 a year I could not afford the truck. In summation if you like the go power and or tow anything other than that bass boat I'd get the 3.73 and pay for the loss of MAYBE 2MPG be it a Chevy, Ford, Dodge, whatever. If you are after maximum MPG and only tow that boat the 3.55 will more than do the job. My 2 cents worth on buying what you really want :)

  2. 8/30/2007 3:45:00 PM Submitted by basskiller2 ( from KY says ok, next question or rephrase
    if i am towing, how much would the 3.73 vs the 3.55 compare when stepping on the gas from a dead stop or pullin the boat out of the water? what about say pulling the boat on the interstate and especially up a hill on the interstate? is the only difference in gas mileage or is there a advantage, power advatage by getting the 3.73. or can you not notice the differnce? thanks.

  3. 8/30/2007 3:54:00 PM Submitted by MikeF from FL says with all things being equal
    The 3.73 gears will give you a 5% higher torgue multiplication.

  4. 8/30/2007 5:00:00 PM Submitted by beartrap from GA says they equip most trucks with 3.55 for a reason
    that being that they will get a little better gas mileage(doesn't rev your engine as high) and it's a good all around ratio for majority of use....I've got 3.42 in my truck(GMC) and i haven't ever seen a ramp that truck won't pull my boat up and you won't either.....if you live in mountains or pull heavy loads or use truck primarily for towing,the 3.73 would make sense....when you're not towing your boat,it's gonna cost you couple miles per gallon(about $5.00) everytime you fill up..

  5. 8/30/2007 6:22:00 PM Submitted by JohnM from TN says I agree with some of what BT says
    I agree with the ratio being an all around gear and it'll do what most need. As far as the 5.00 EVERY time you fill up? If you drove ALL freeway miles EVERY tank then yes it may. How many of us drive all highway miles? If you look at the "city mileage" between the two gears it MAY be 1MPG difference and in my experience with lots of trucks I have found the lower gears get the same if not better around town. If I drove all or mostly highway miles and wanted a comfortable truck to pull a boat and use as a truck on occasion I'd give an Avalanche another try (that is if Chevy would get somwhat in my price range on them). I got 20 MPG Hwy with mine 3.73 gears, as usual though I got a bad one grrrrrrrrr. I would also keep in mind Chevy and Ford have those tall gears in a constant war for fleet sales. 1MPG may not affect us much but spread that out over a fleet of 200 plus vehicles and now that can really add up. I'd drive em both, dirve em hard off the line and see what says "buy me".

  6. 8/30/2007 6:49:00 PM Submitted by Roby ( from TX says 3.55
    I bought am 04 with the 5.4 and 3.55 gears. I pulled an old Robalo for a couple years that weighed in closed to 6,000 lbs, no sweat. 18-19 mpg is the best I have seen on the road. 10 mpg towing my 23 Gulfcoast. The 5.4 has plenty of low end torque. Make sure you get limited slip, that would be a greater concern than 3.55 vs. 3.73. I prefered the 3.55's because I used to drive the truck to work a whole lot more than I towed. Now I only use it for towing. The civic passes a whole lot more gas stations...

  7. 8/30/2007 8:28:00 PM Submitted by Basskiller2 ( from KY says gas mileage is not a concern...
    more of a concern is will the 3.55 pull the boat equally if not better than the 3.73. i agree that the 3.55 will be cheaper on gas but i am more concerned about the pulling power at stop and on the interstate. is there a difference? will the 3.55 effect the longevity of the engine when it reaches 100k or 150k miles. meaning will the engine wear out faster in the 3.55?

  8. 8/30/2007 11:36:00 PM Submitted by Tomcat ( from KY says I have the 5.4 and 3.73
    My F150 4x4 has the 5.4 with 3:73 gears and towing package. Tow a 19 ft. boat. Gas mileage isn't great whether towing or not, but when towing, it's like the boat isn't even there. The 5.4 is more than enough. But since I use it as my everyday vehicle more than towing, I would rather have the 3:55 gears with the 5.4. Bought the truck used, so I didn't have much of a choice, but still satisfied with the 3:73 gears. I don't tow that much or anything heavier than the boat. Gas mileage is less with the 3:73, but not enough to be concerned about. No doubt the 3:73 is best for towing. If most of your use will be non-towing, I'd go with the 3:55; if mostly towing, then go with 3:73. I've had both, just my opinion. Get what you're happy with.

  9. 8/31/2007 5:24:00 AM Submitted by Curt ( from FL says 07 Ford
    Got a 07 Lariat w/3.55 and 5.4 Pull a 18 1/2 hydra sport f/s Getting 20 mpg on road 14 when pulling boat also have limited slip No problem with get up and go Be sure you get the tow package it has the tranny cooler Great truck Curt

  10. 8/31/2007 7:50:00 AM Submitted by MikeF from FL says again
    The 3.73 will tow at least 5% better; you have to decide if that's signifigant enough for you to notice a difference. I think it is, but like the guys said the truck will tow the boat fine either way.

    One thing I have trouble understanding is why people who want both better fuel mileage when not towing and better towing don't just take their truck out of overdrive. Going down one gear in the transmission has more of an effect on the final drive ratio (trans gear times diff gear) than going from 3.55 to 3.73. Do the math, towing is all about torque multiplication.

    One other point to consider is the RPM range when you are towing. If you look at a torque curve you will see a significant difference in the available torgue at lower RPM. To get the best tow you would want your engine producing max torque so the 3.73 would probably put your RPM range closer to max torque and instead of 5% better it might be 10% better. That's why my first post said "with all things being equal".

  11. 9/1/2007 11:53:00 AM Submitted by BASSMAN IA. from IA says basskiller2
    If it's just towing a boat look at roby's post, the boat he is pulling weighs twice what yours does. I have a 5.4 ( 2 valves per cyl) with 3.55 ratio, that is the standard gear in a F150 2WD with the tow pkg. I tow a 21 ft. Charger, I have never had a problem yet. To answer your question about longevity of the motor---- the 3.73's are going turn the engine a few hundred more rpms----- in both drive and overdrive then the 3.55's

  12. 9/1/2007 4:20:00 PM Submitted by fishnfool ( from GA says Tires
    If you are going to run stock size tires it would be fine. But if you go up in size at all it will drop the ratio down even lower. If you were going up in size or going to be towing alot,I would definetly consider the 3.73's at minimum.

  13. 9/5/2007 4:24:00 PM Submitted by steve s ( from IN says 3.73
    I have a 2006 F-150 with a 5.4L, 3.73 gears and stock 17" wheels/tires. It turns 2000 rpm at 70 mph in overdrive. I can tow my 196 Champion in overdrive down to 55 mph without it wanting to downshift all the time, then I have to lock it out of OD. You might put slightly less wear and tear on the engine with 3.55 gears, but the wear you would put on the transmission if it is constantly shifting would negate any benefit. I bought my truck for towing only, so I went with the 3.73. Even if it were mostly for commuting and occasionally towing, I probably would have made the same choice. The 5.4L gets bad gas mileage, but it makes good power. No matter what gear ratio you get, it will still get bad gas mileage and make good power.

  14. 9/6/2007 6:10:00 AM Submitted by Bro ( from FL says go with the 355

    and save the gas money. the 5.4 is more than enough to yank your tiny 18 footer up to speed on the interstate and handle everything you listed with no issues.

    sure it will downshift some in the hills of Kentucky but so will the 373.

    those are officially listed as some big arse hills.

Go to next message
Go to previous message

Notify board monitor that this message contains inappropriate content

Great Deals on Fishing Equipment!
Shimano Reels St. Croix Rods Spinner Baits Daiwa Reels


To post a followup to this subject use the following form:

(Sponsors/Supporters only)

Email Address (mandatory for non-subscribers and non-registered users!):




Advertising/Sponsor Information

Register to post messages and reports


Subscribers don't receive these ads

Fishing Reports
BFHP Articles
Fishing News
Upcoming Events
Rally Page
BFHP Surveys
Fishing Tactics
Places to Fish
Other Topics
Product Evaluations

Boat Ramp Stories
Trailers & Towing
Boats For Sale
Tournament Tactics
Striped Bass

Fly Fishing
Saltwater Fishing
Non-Fishing 2
Political Hook
Tall Tales, Fiction & Legend
Complete Listing of Boards
Copyright © WMI, Inc. 1995-2017. All rights reserved.
This message board created and maintained by: WebMasters International, Inc. (WMI) address mail to

WMI disclaimer
Privacy Statement