im a college student so time and money are big probs and i dont think i could do that myself prolly not too cheap either

 

Save your pennies and get a 5.4.....


.

 

http://www.4lo.com/calc/gearratio.htm

Crank your tire size into this to see what the rpm's will be. Use 0.7 for tranny ratio (overdrive with converter locked up) and 1 for transfer case ratio. You can check at different speeds and with different axle ratios.

That said, 4.6's thrive on high rpm's and 4.56's are not too extreme even with stock tires. The torque isn't even peaking till 3500 to 4000 rpm - where the 5.4 peaks around 2500. The 4.6 is a car engine, the 5.4 is a truck engine.

I don't care how well you can get it to breathe - for pulling a heavy truck around, there's no substitute for cubic inches and long stroke. You can compensate a lot for this by keeping the rpm's up higher, which means gears.

 

Thanks glc, thats what i was thinking but you dont think that riding around on hwy doing 70 75 will hurt the engine will it....i mean rpms tached up the whole time your driving wouldnt it?

 

It won't hurt the engine as such... You will want to keep up with the maintenance and all of course... Over the long haul of running over 100,000 miles or so, you might have a bit more wear and tear from running at higher rpms compared to an engine that just looped along in OD all it's life, but that's only speculation on my part..

When I tow my travel trailer, I'm usually only in 3rd (OD off) and pulling around 2300-2500 rpms for hours at a time and I've got over 200,000 miles on my 5.4...

If you run around in 3rd all the time, it would be no different then running around in OD with the 4.56 gears for the most part...

Gotta "pay to play", so running at the higher rpms is part of the 'play', so the 'pay' part will be some additional wear and tear..

But, simply running your engine at a higher rpm will not make it immediately implode on itself either!

That's just my take on it however....

Mitch

 

Thanks i appreciate the advice! No i wasn't really worried about it hurting the engine immediatly just shortening the life span of the engine and specially since its a 4.6 instead of my old 5.4 but i guess you are right "pay to play" it'll be worth it!

 

Here's what my heatsoaked 4.6 laid down before gears and a few minor tweaks. I know it has more in it, but Mike T. won't touch my tunes these days.



Yup, more peak HP at the wheels than your 5.4 had at the crank. I think my weak torque #'s must have been due to the lack of gears and maybe 3rd. gear run rather than 4th.

If you have money to spend, I'd say the appropriate PI heads with cams, fresh ignition components & O2's, longtubes, intake, custom tuning, and most importantly gears. With 33's and an auto tranny, I'd go 4.56.

 

i just got the price back on doing front and rear 3.73's and the place i took it too wants almost $1800 dollars dont kno too too much bout how much work it is but this really does seem like a ridicules price to i was thinkin $1000 give or take a couple hundred? What would ya'll suggest? Is this somethin a novice should even attempt to tackle? (i wouldnt think so) Does anyone think i could just leave my stock gears in or is regearing a MUST with 4.6 and 35"s?

 

I think regearing is a must for you to get what you want, and forget 3.73's, go 4.56. That price is a bit high but not out of line, you gotta pay to play.

With 35's, you would be doing 2300 rpm at 75 in OD with 4.56's. That's nothing, as I said, the torque on a 4.6 peaks between 3500 and 4000.

 

alright thanks man! One more thing...if i regear the rear and leave the front alone will it still be alrigth to put in 4wd?

 

Nope!

 

that sucks! gotta scrap all my plans now! Thats too much to spend on regearing an old truck after thinkin about it! I need sum donations or sumthin guys!

 

Yea, IF I wanted to re-gear, I would have to do it myself. I like my 3.55's tho and she's got plenty of power. Any more and I would just be breaking things, -like the bank .. Ahhh, it's only money right

 

Right! that 4.6 just isnt a 5.4 and specially with 33's or 35's!

 

35's? You won't even notice the change to 3.73's. If you have an auto tranny, I'd go at least 4.88 if they offer them in reverse cut. You can usually find pretty good deals on gears, but the labor sucks. I paid $350 rear and $500 front just in labor. Shop around. OYu don't have to find an offroad shop. A racing outfit with Mustang experience will do just as good if they aren't afraid to pull the front diff.