/hello all, ive gone back and forth on what i wanted to do to finish up my trucks 5.0 performance. all in all i think i have a pretty potent combo, consisting of comps 31-255-5 with 1.7 crane rockers some gt40s for heads, some longtubes with full true dual exhaust. a hotter ignition and a k&n panel filter. and finally now i got my AOD transmission rebuilt with a new shift kit. and now just today my 4.10 gears came in from summit racing. right now the trucks pretty darn quick with its 3.55 gears and open differential. axle code 19, but my question is will it be a big acceleration difference with the 4.10s? even with an open differential? i rarely drive this truck on the highway, maybe 3 times a year. so highway mpgs dont really matter, ive heard 4.10s can help city mpg so i hope that will be true, but i just want to know if anyone has experience putting 4.10s behind a beefed up 5.0, and if its not too much of a pain to install them myself,
thanks for any advice guys!

 

I'm willing to bet that when you put those gears in, you'll feel like it's more of an improvement than when you put the cam in. It'll feel like a whole different truck. Should take off pretty smooth, probably light up the tire pretty easily too. You should probably find a L/S unit for the rear end so that you can make the most of the power you've got. No sense having so much power if you can't keep it to the ground.
I had 4.10 l/s in my truck when I bought it, and put in 3.55 gears and I absolutely hate it. It feels like it sucked all the power out of the truck. So you should be pretty happy with the power boost.

 

yeah im assuming the truck probably makes somewhere in the area of 300hp and 350tq so it would be nice to actually be able to use more of it ya know, but thats good to hear, because i hate the axle its got now, im a bit tired of the old one wheel peel. i see you suggest a l/s unit. can you get those new from a parts store maybe? or would i have to search the yards? and that being said, did you switch your gears? or did you have a shop do it? im just trying to see if its cost worthy to pay to have it done or it i can handle it myself. thanks for you reply

 

I would assume a parts store could order one, or summit probably carries it, but it would probably be cheaper to just get a unit out of a junkyard, although it would be used and would probably need the clutches replaced. When you put it in, add friction modifier. That, you can get at a parts store.
If you've never put in gears, don't do it yourself, have a shop do it. I had my uncle walk me through how to do it, I think I would have messed it all up otherwise. If a shop does it, and they mess it up, they'll be paying for it, not you.

 

okay that helps alot, i myself have never installed gears so i get some quotes around to put them in, so in all for parts being that i already have the gears, all else i would need is the L/S unit and the friction modifier?

 

I believe so. I mean, you could have your whole rear end rebuilt at the same time, but not really necessary.
I guess I never asked, your truck is 2 wheel drive right?
If it is, then I'm pretty sure you're good to go.

 

yeah its a 2wd. it would suck if it was a 4x4 because then id have to do both axles. but ok thanks for the info, im gunna look up the parts now, the sooner i get those 3.55s outa there the better, and im really looking forward to putting the hammer down the the 4.10s in the back

 

Definitely get some kind of traction diff for that axle, if you think you got a 1-wheel peel monster now just wait....

The Ford Tracklok is a decent street diff if it gets a rebuild with restacked clutch packs and is shimmed to put more preload on the spring. With that setup you'll have solid 2wd all the time and I doubt you'll find anything cheaper, these difffs aren't too expensive new and a rebuild kit is only about $100.

 

just went on summit racing and ponied up the extra money and got a new ford racing traction-Lok differential from summit racing, paid $250 for that, and i got the new gears for $157. now i just have to find somewhere to have it installed soon. after that, watch out lightnings... haha

 

Good deal. Let us know how it turns out when its all done.

 

I sure will! Thanks for the help guys