Crawl/rock mode causes diff make noise , normal?

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Badgertits

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Good thing on the Raptor vs. all other 1/2 tons available (as far as I know) - it is the ONLY one that can run in true "AWD" - there's a separate input shaft for the AWD function of the transfer case I believe vs. a pseudo partially engaged 4wd-hi "auto" mode that other 1/2 tons employ (including regular F150s) Where the axles are locked but the hubs do not engage until slippage is sensed.....in reality although you supposedly can drive in 4 "auto" in dry conditions I believe there is still concern for excessive wear & binding especially in full lock turns....additionally, there's a lag between when the front traction is needed & when the front hubs actually engage (at least on my GMC trucks) which could make the "help" of front drive traction a hinderance if its not engaging at the appropriate time. This is not a concern w/ the Raptor in 4A - you should be able to run that way all day every day wet dry rain mud grass sand snow etc etc etc

Its a nice feature & once you get used to driving the truck in general w/ how the tranny shifts & the weight balance etc. running it hard in Sport mode + 4A w/ traction control off = most fun driving experience possible in a full size pickup
 

highway420

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Good thing on the Raptor vs. all other 1/2 tons available (as far as I know) - it is the ONLY one that can run in true "AWD" - there's a separate input shaft for the AWD function of the transfer case I believe vs. a pseudo partially engaged 4wd-hi "auto" mode that other 1/2 tons employ (including regular F150s) Where the axles are locked but the hubs do not engage until slippage is sensed.....in reality although you supposedly can drive in 4 "auto" in dry conditions I believe there is still concern for excessive wear & binding especially in full lock turns....additionally, there's a lag between when the front traction is needed & when the front hubs actually engage (at least on my GMC trucks) which could make the "help" of front drive traction a hinderance if its not engaging at the appropriate time. This is not a concern w/ the Raptor in 4A - you should be able to run that way all day every day wet dry rain mud grass sand snow etc etc etc

Its a nice feature & once you get used to driving the truck in general w/ how the tranny shifts & the weight balance etc. running it hard in Sport mode + 4A w/ traction control off = most fun driving experience possible in a full size pickup

I have driven (and am currently) driving in the 4A mode. With a tune, it burns the back tires too easily and like how it comes out of the side streets into main blvd. in all wheel.

It doesn't continually lock/unlock hubs though. it's in the Transfer case. It uses clutches to engage front drive instead of a hard locked connection. Kind of like the gears in manual. The shaft is locked to the gear in 4wd. in all-wheel, it's a clutch system that allows the forgiveness needed to drive on pavement. I make u-turns, regular turns, and park in side structure at work and hear no sounds of binding, sticking, tire screeching or hopping.

To better see it, put the " Power Distribution " screen in instrument panel while in 4A and take a cruise on highway. You'll notice at cruising, only back shows up and when you step on it, it will show all four. I love this mode, and use it all the time when it rains here in So Cal. It's slippery here when does rain....cause it never rains here! So all that wonderful oil comes up to play. And, plus it's a truck with not much weight in back. Best reason is... it's just frickin fun!! (and somewhat safer.. )

On that note, do not use 4 low or even regular 4wd on dry pavement. As others stated, not good at all.
 

Badgertits

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I have driven (and am currently) driving in the 4A mode. With a tune, it burns the back tires too easily and like how it comes out of the side streets into main blvd. in all wheel.

It doesn't continually lock/unlock hubs though. it's in the Transfer case. It uses clutches to engage front drive instead of a hard locked connection. Kind of like the gears in manual. The shaft is locked to the gear in 4wd. in all-wheel, it's a clutch system that allows the forgiveness needed to drive on pavement. I make u-turns, regular turns, and park in side structure at work and hear no sounds of binding, sticking, tire screeching or hopping.

To better see it, put the " Power Distribution " screen in instrument panel while in 4A and take a cruise on highway. You'll notice at cruising, only back shows up and when you step on it, it will show all four. I love this mode, and use it all the time when it rains here in So Cal. It's slippery here when does rain....cause it never rains here! So all that wonderful oil comes up to play. And, plus it's a truck with not much weight in back. Best reason is... it's just frickin fun!! (and somewhat safer.. )

On that note, do not use 4 low or even regular 4wd on dry pavement. As others stated, not good at all.

Yeah I knew it doesn’t continuously lock/unlock the hubs, that’s what the all the fake 4A systems do on 1/2 tons, knew it worked in the transfer case just wasn’t 100% clear tho how it did so- the clutch system makers sense, I thought there was a separate dedicated prop shaft or something.

At any rate- yeah- best of both world w/ the Raptor AWD, 4WD or 2Wd
 

Peterb

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is there a torsen in the transfer case to accomplish 4a?

i know the front dif has a torsen thanks
 

jabroni619

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is there a torsen in the transfer case to accomplish 4a?

i know the front dif has a torsen thanks

No, 4A is accomplished by using a wet clutch pack in the transfer case that allows the necessary slippage to occur to keep from binding
 

highway420

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I like seeing the insides... here's a pic from when they first announced the Gen 2.


023-raptor-transfercase-jpg__167276_.jpg

If you look carefully, you can see next to the chain on top side, on the right of chain, would be the 4wd connection (hard/locked) and to left of it, is the clutch pack. I may be wrong on the actual location of clutches, but makes sense there. Maybe it's on the right side on the input side.
I know for sure the connection for 4wd is the syncro next to on right though. Anyone seen this in person/close up?

I love the little hand wheel they put so you could rotate it..lol
 

MDJAK

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So someone said cause he has a tune he likes 4A as otherwise the rears break loose too easily. That’s the case in stock form too if you step on it.

So, yes, I acted immaturely at a light recently. Road I take home narrows from 2 to 1 lane so it’s usually a race to be first. I rarely care but it’s 7 miles to home form there and recently they upped the limit from 40 to 55 and most dopes ignore that new sign and do 40 to 45 which makes me nuts.

So this one time I put it in Sport, 4A, and stepped on it. The feeling was not a good one. It was like bumping, etc,

As the rears lost traction and the fronts grabbed, it was not smooth but actually kind of scary. I thought it was rough shifts but my tranny is and has always been very smooth.

Bottom line: I kicked the 3 Series’ ass.
 
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