I have looked through the site for answers but only see threads about older engines not the 5.0.

I have a 2011 SCrew 4x4 with 5.0 and the truck came with 3.55 gears. My last truck Dodge Hemi had 3.73 gears so I was wondering how much of a difference will this make? I see on Ford site my same truck with 3.73 can haul 1500lbs more than what mine can.

I haul a bass boat 2-4 times a month weighing around 3,500lbs.

I also am looking at a travel trailer that will weigh around 5,500lbs when loaded.

I would also like to add 33" tires later on.

Should I upgrade the gear ratio and if so how much does something like that cost? Will I void warranty.

Thanks for your help in advance.

 

You should be ok......its when you get the tire size past 34" is when you really loose mpgs and put more strain on the drive train.....

 

I don't think you'll notice any difference.

 

The biggest mistake will be the lack of Max Tow and the higher payload. You might be able to get by. But Max Tow would have been better for the 6k travel trailer. Do you need 33's? Yes, you could void the warranty but probably won't unless something goes wrong. You could also trade it in on a 2012 with a premium engine, 3.73, Max Tow, SuperCrew HD Payload package, etc.

 

The 5.0 is a strong engine with plenty of HP and TQ., so I agree you should be fine, especially with the new 6 spd. transmission.

I have 3.55's on my current truck and that combined with the anemic 4.6L and 4 spd. transmission makes using the A/C and cruise control impossible here in SW Virginia (lack of power resulting in constant/frequent downshifts).

You have a great truck, dont worry about it.

 

can you switch gears? yes, should be about $1500. before you spend that see how it does, no need to knock on your truck until it gives you a reason to or spend all of that money.

will it void warranty? you will void your warranty relating with gears, shouldn't void anything else.

 

I would seriously wait on the larger/heavier tires if you plan to tow a full-walled travel trailer. The 3.55 axle is far better than my 5.4L 4-spd and 3.73. It's better than if I had 4.56 axle.

I agree about payload. That's the limit most RVers hit well before tow rating of a half ton. Max tow package is best among the competition, and the HD payload rules. Forces you into the EB, though.

 

With the new 6 spd trans and it's wide range of ratios, the 3.55 will be great. Stock tires on 20s are 275/55-20 and they are near 32" tall.

It'll be fine. You still have a larger tow rating than some 3/4 ton trucks years ago did.

 

Thanks guys. I will hook up my boat this weekend to the truck for the first time and let you know how it does.

 

They will do OK but I still think the 3.73 is better. Sometimes my 3.55 feel's like a 3.31!

 

^^^ What he said. My truck has the chrome pkg w/18" rims. The 275/65-18 GY tires spec out at 32.2" tall, but an LT 33" tire will also weigh a little bit more. Try it first before you re-gear like 06YZ250f said.

 

If you don't plan on getting larger diameter wheels nor racing on the drag strip every weekend, you are just fine so really don't sweat it as much as you are doing right now!

 

I think you will be fine and have plenty of power/gearing to tow what ever you want..... 6spd autos are great for this...

BUT I will say.....I recently switched to 33"s(heavy/wide 305/55/20s) and it made a very noticeable difference in part throttle acceleration (and ofcourse full throttle).... More of a difference then I thought it would...especially with 3.73s... Its still VERY liveable and better then most 6000lb trucks accelerate I'm sure but.... it definitely needed more throttle application to get moving then before with the stock 275/65/18s (32")...

I havent measured fuel mileage with the new wheels/tires but it definitely took a dump.

 

If I did go up to 33" tires it would be 275/70/18 on stock rims so they shouldn't weigh much more and have will have the same width of tire.

Looks like for what I will be using it for 3.55 will be fine and especially not worth upgrading to 3.73 for $1,500.00 and chance of voiding warranty.

I could always get a F150 Boss 302 KIT for $1,200 if I really feel I need to do something down the road.

 

Yes, you will void you warranty.

If you plan on towing anything around 6000 to 7000 lbs with a full height sidewall as a travel trailer, I would not put on a 33" tire. If doing so, I would get an FX4 with the 4.10 gearing.

For your 5.0L, I would had gone to the 3.73 for towing but if you keep your load under your tow rating, about 80% of tow rating, you should be fine. Remember the tow ratings are usually for car trailers and other low profile trailers. That's why Ford recommends a front trailer profile of only 65 square feet. If you're going to go with a travel trailer, you really shouldn't tow anymore than 80% of the tow rating and if going up hills or towing in high elevations, even lower than that.

You will be on your limit for sure, but you can try it. OR trade to a truck that's more geared for towing.

If you are going to tow a travel trailer, don't even consider putting on bigger tires unless you are prepared to put in some aggressive gearing that will void the warranty.

IMO, you best options are to stay light when towing or upgrade to a different truck with the Ecoboost.

Good luck.