so i got a little wild last night with the 4.9 and found out two things 1. new brakes mean full throttle no wheelspin but thats a different thing. and 2 when i let off the brake the motor roasted both of em but it came factory with an open diff and 3.08s. my question is will an open diff spin both of them or has someone swapped in a limited slip? i tired it on gravel and they both spun to but i noticed something that i couldnt on the pavement, one kicked up a little more gravel than the other? any help would be grateful, thanks guys

 

Mine does the exact same thing...I honestly have 0 idea on it.

I know how a differential works, and *Technically* it should only spin 1 tire, period.

I've also noticed if I back up about 20-25' and then pull forward, it sorta "Locks" the 2 wheels together as a posi-setup for about 50'...

Or if in deep mud, put it in reverse, and turn the tires backwards a bit, then put it in 2nd...Pulls me through everytime.

The reason I use 2nd over 1st, is it doesn't spike the rpm's and cause it to lose traction as quickly.

 

hey wes did you ever figure out you deceleration problem? i was driving the 5.0 than hopped in the 4.9 (both e4ods) and the 4.9 definitely has waaaayyy more engine braking than the 5.0 which i cant explain.

 

Yes, an open diff will spin both tires sometimes.

 

A friend of mine mentioned reading something about 4.9's having a setup with the Injectors, being the main deal behind the extra EB...

I just quit wondering and accepted it...Hell, everything else is diesel-esque..Why not that too?

My engine bay even sorta looks like a diesel setup (Minus the plugs, etc), as I have the dual battery trays, coolant reservoir, etc from a 7.3 truck..

 

makes sense

 

The I6 has bigger pistons and a heavier crankshaft so it's behaving exactly as physics says it should... it's slower to accelerate or decelerate or in other words has more flywheel effect.

P.S. An open diff will spin both tires if traction is the same under both, put one in the grass and the other on bare pavement and I bet you'll get a different result.

 

That makes perfect sense; Except that in my truck, when decelerating, it's like you literally flip a Jacobs Engine Brake on Stage 1....

After a certain rpm (About 1,200) it is like you turned the switch back off.

My logic tells me something "Else" is going on, on top of what you said.

 

It must be witchcraft!

 

Nobody ever got wild with a 4.9. Even just a little wild, especially with 3.08 open gears. At this point, I don't know how credible you are.

 

You've never driven my truck on a wet road (Needing tires in a few months)...

It gets...Interesting.. At times, to say the least. lol

 

really tell that to the 50 high schoolers who watch me leave double s es in the parking lot

 

Yeah, 50 highschoolers are going to be so much more credible than the guy who got "wild" with a 300.

 

hey its wild in its own little area. i mean compared to a 351 it probably isnt that wild but hey i have a lot of fun with it and it burns em well enough for me

 

Even the old farts at the nursing home get a little "Wild" every now and then.