arkansawyer

The 6 speed transmission is a key piece to what the late model trucks can
do. 20+mpg, tow several tons, get up to speed on an interstate onramp, while weighing over 5,000 pounds.
4.17:1 low gear X 3.73 rear axle = 15.55 overall gear ratio
.69:1 6th gear X 3.73 rear axle = 2.57 overall gear ratio

The old TH350,TH400, C4, and C6 automatics had 2.46-2.52 low gear ratios and 1:1 high gear ratios. The converters didn't lock up in high gear, which made things worse. There had to be a compromise between pulling power/acceleration and highway mpg.
Your old TH350 had a 2.52:1 low X 2.73? rear axle = 6.87 overall

I'll have to look, but I think 70mph is only about 2,000rpm with my 3.73 gear. There's only so much power available at low rpm. Gearing too high makes an engine lug and work harder than it should.

My '78 grand prix came with 2.42 rear end gears and turned about 2,100 on the highway. Acceleration was pretty leisurely with the stock 301 4 barrel engine.

OddBall

Why are you posting here if you dislike it so much?


Well, simply having a larger chunk of metal between the combustion chamber and coolant passage isn't a valid comparison. Engines today are built to much stricter tolerances, the engineers have access to better materials, computing power that is many orders of magnitude more powerful than anything that came out of the carburation era. The engines adapt to your individual driving style, adjust fuel air ratio constantly, etc etc etc... I could go on and on about the differences between new and old.

Notice how the EB's can run just fine all day long and 87 RON Unleaded and not need any cool down period after high speed operation? Try that on a 70's, 80's or even 90's era turbocharged engine, excluding diesels and see how long the turbo lasts.

The engines of the 70's and 80's were grossly inefficient, anemic polluters. Really, if you want to tow anything serious I wouldn't use an F150 or any other light duty 1/2 ton pickup. I'd be starting at an F250 and working up from there. The fact that we CAN tow as much as these trucks are capable of is a testament to how far we've gotten away from the old inefficient designs. Did those trucks have Sat Nav and all the other luxuries we have available today? Not to mention, did they have ABS, stability, traction control and return the fuel economy? Not even close. Could they accelerate in anything that remotely resembles what these can do today? Nope, not even close.

In fact it's us, the consumer, that made the demands on auto manufacturers for what we have today. We also created the litigation monster that is prevalent everywhere today as well.

Sure there are some potentially serious issues with this 1st gen EB in the F150 but it's teething pains and we're the guinea pigs. I'm not terribly thrilled with that prospect but auto manufacturers aren't the only ones using us as a test bed for a production product.

Get used to it.

packplantpath

I didn't believer your numbers, but holy crap, the 2013's are rated about 1000 lbs higher than the equivalent 2012 setup.

What gives?

schrod

I don't know except before I took delivery I checked the tow ratings chart and the max-tow with 3.73 axle is 17100 GCWR vs tow pkg. with 3.31 axle @ 15100. Same way on the tow ratings with the max-tow with 3.73 @ 11,200 and the tow pkg with 3.31 @ 9200. Both vehicles Eco platinum screw 4X4 with 145 wheelbase.
I check speedo on the way to dealer when going to trade and the 3.73 axle @ 65 mph was right on 2000 rpm's. Coming home with the 3.31 @ 65 mph was 1700 rpm's.

13'TwinScrew

Just to add, I'm pretty sure my 13' has a 9700 lb tow capacity with the tow package. I towed about 4K lbs and about a total of 470lbs of gear in the cab to WV this weekend and averaged 10.8 going and 12.7 coming back at around 70-75MPH avg speeds and an occasional 85mph. Engine never really worked hard and this was with some "Crazy wind" the entire trip.

So I think that anything under 3.55 for consistent towing would be too anemic.

schrod

Yours would have to be a super crew with 157 wheelbase with 4X2 for 9700 lbs towing capacity. Yours would be 9500 with 157 wheelbase and 4X4 with super crew. Sorry but this is off the tow chart. So according to chart you can only safely pull 300 lbs more than my 3.31 rear end.

Sitedrifter

My SRT10 Ram had serious gear ratio. 4.56:1 rear axle which helped propel my truck 0-60 in under 5 seconds and my best 1/4 time of 12.99 at 108mph.

My post is meaningless to the thread, I just wanted to say there was a truck made with a serious axle ratio but... 0000lbs of towing capacity. Yep ZERO.. LOL

Centexguy

Fixed it for ya.

13'TwinScrew

We are both incorrect by 100lbs. Mine is a 4x4 supercrew 145" wheelbase with a 9600 lbs capacity. My post is my opinion only and going through the mountains in WV, 3.31 would have worked a lot harder, as the 3.55 was "fine" if I would have had 9,000lbs or more it would've been working pretty hard...too hard IMHO for a 3.31. Like I said just my opinion but the 3.55 would be the lowest I would consider for towing 8000lbs or more regulary .

http://www.ford.com/resources/ford/g...rv&tt_f150.pdf

montanaman

I wouldn't want a higher gear than the 3.55's, because pulling a equipment trailer weighing 3,300 lbs, with a Bobcat S175 on it (6550#) is all my truck wants to do, and I'm a fanatic about having the correct tongue height, trailer brake controller set right, etc.

And FOMOCO only rates my truck for 7800# - if I had 3.73's it would be rated over 9000#.

If I start pulling more, I'll trade my beloved 1/2 ton up for a 6.2 Super Duty I guess.