4 wheel drive..., why?
Senior Member
Joined: Oct 2001
Posts: 250
Likes: 0
4wd
It's for when you can't move forward any further or for when you know you soon won't be able to. I have found it can also aid in vehicle stability in snow and ICE where you have limited forward traction as long as you don't try to flagrantly violate the laws of physics. But it is a supplement to sane driving, not a replacement. I will frequently use it in slush, light snow, and ice where I can actually move along in 2wd but accidental over-application of the throttle when starting off or turning can cause the rear end to kick loose.
I drove like a maniac much of the time when the roads are dry and my gf frequently reaches for the 'oh-*****' handle.
I do a complete 180 with my driving style when visibility and traction gets poor. I have absolutely no problem puttering along like a grandma and getting passed all the time when road conditions are less than ideal for fast driving. IF it's so bad that I feel the need to flip the switch than it's also time to cut my normal speeds.
To the OP: If the wife has a fear of wet leaves I strongly suggest encouraging her to use her own vehicle more often.
I drove like a maniac much of the time when the roads are dry and my gf frequently reaches for the 'oh-*****' handle.
I do a complete 180 with my driving style when visibility and traction gets poor. I have absolutely no problem puttering along like a grandma and getting passed all the time when road conditions are less than ideal for fast driving. IF it's so bad that I feel the need to flip the switch than it's also time to cut my normal speeds.
To the OP: If the wife has a fear of wet leaves I strongly suggest encouraging her to use her own vehicle more often.
Technical Article Contributor
Joined: Nov 2002
Posts: 2,804
Likes: 9
From: Wisconsin
Right, I don't disagree that the front tires and rear tires have different radii. What you're numbers show is that there is a speed difference of "2" between the fronts and rears.
However, another way of looking at it is that there is also a speed difference of "2" between the inner and outer tires, of both the fronts and rears (gotta subtract to get differences...)
R rear - L rear = 3 - 1 = 2
R front - L front = 4 - 2 = 2
Obviously the right front isn't travelling 4 times as fast as the left rear, so those numbers don't really mean a whole lot when it comes to real world results.
It would ultimately depend on the size of the tire (rotational speed differences would be affected by tire size, smaller diameter tires would rotate more for a given speed difference than larger tires), as well as vehicle width and length. At different configurations, you could conceivable get wheel hop from either front to rear, or inner to outer wheel speed differences.
However, another way of looking at it is that there is also a speed difference of "2" between the inner and outer tires, of both the fronts and rears (gotta subtract to get differences...)
R rear - L rear = 3 - 1 = 2
R front - L front = 4 - 2 = 2
Obviously the right front isn't travelling 4 times as fast as the left rear, so those numbers don't really mean a whole lot when it comes to real world results.
It would ultimately depend on the size of the tire (rotational speed differences would be affected by tire size, smaller diameter tires would rotate more for a given speed difference than larger tires), as well as vehicle width and length. At different configurations, you could conceivable get wheel hop from either front to rear, or inner to outer wheel speed differences.
Even the limited slip differential is a differential. You can get rear ends which will wheel hop, but they are not an option on a F150.
- NCSU
Some times I wish I didn't know the difference. It was a lot more fun when I was younger, and pulling people out was more fun before cell phones.
Senior Member
Joined: Jul 2009
Posts: 219
Likes: 0
From: cleveland.ohio
This thread really needs to be closed out.
The comments seem to be getting dumber and dumber..but said with such conviction.
I tried to explain this but some of the arm chair mechanics are like kids that just yell louder when there wrong.I know what your thinking,how would I know,after all I'm just a certified master tech for the past 23 that certaintly doesn't carry as much weight as lets say..a truck driver or CPA.
So..will someone PLEASE back up there statements with something other than here say.
I'm gonna put a link here..please read it.
http://www.denalitrucks.com/documents/TL_Jan03.pdf
I'm sure most mechanics are familiar with this and by no means am I trying to insult you.But some of these comment are so off the wall made by guys that own but don't know how to repair.
And before anyone starts flaming and yelling please back up what your saying with some facts...hard cold facts.Also why are we even at this point..the original question was pretty much answered long ago..with the bottom line being that its normal of 4 wheel drives on dry pavement to skip..why is besides the point..it happens.Can we please at least all agree on that ?
Oh and by the way..I'v raced cars for years and 2 rear wheel drive drag cars (1/4 mile cars)get wheel hop.(NOT ALL,BUT A LOT DEPENDING ON THE SET UP) The rear ends on many are locked giving power to both wheels..no slipage..and when moving off the trailer as most hot rodders will tell you they get wheel hope.And these are 2 wheel drive cars. ALSO in street cars limited slips diffs NEED an additve to aid in the slipage..if not present they will also lock up..and these are 2 wheel drive cars.Although rare..it does happen when backyard mechainics dont read the manual and ad the wrong fluid.
People are correct in stating that NORMAL 2 wheel drive vehicles are not locked and have a differential to transfer power and prevent the axles from turning at the same speeds when turning.. when working properly..key words..when working properly.
P.S. This isn't aimed at anyone so please no one take this as a personal attack..its not.
While I'm at it..heres a pic of my 49 merc.Its a drag car..429cid powered by ford..set up to go straight and do it fast.Rear end has the spider gears welded for going straight..not street legal..wheels hop when loading on the trailer or turning sharp in the drive.I do have a bit of experience with cars.
The comments seem to be getting dumber and dumber..but said with such conviction.
I tried to explain this but some of the arm chair mechanics are like kids that just yell louder when there wrong.I know what your thinking,how would I know,after all I'm just a certified master tech for the past 23 that certaintly doesn't carry as much weight as lets say..a truck driver or CPA.
So..will someone PLEASE back up there statements with something other than here say.
I'm gonna put a link here..please read it.
http://www.denalitrucks.com/documents/TL_Jan03.pdf
I'm sure most mechanics are familiar with this and by no means am I trying to insult you.But some of these comment are so off the wall made by guys that own but don't know how to repair.
And before anyone starts flaming and yelling please back up what your saying with some facts...hard cold facts.Also why are we even at this point..the original question was pretty much answered long ago..with the bottom line being that its normal of 4 wheel drives on dry pavement to skip..why is besides the point..it happens.Can we please at least all agree on that ?
Oh and by the way..I'v raced cars for years and 2 rear wheel drive drag cars (1/4 mile cars)get wheel hop.(NOT ALL,BUT A LOT DEPENDING ON THE SET UP) The rear ends on many are locked giving power to both wheels..no slipage..and when moving off the trailer as most hot rodders will tell you they get wheel hope.And these are 2 wheel drive cars. ALSO in street cars limited slips diffs NEED an additve to aid in the slipage..if not present they will also lock up..and these are 2 wheel drive cars.Although rare..it does happen when backyard mechainics dont read the manual and ad the wrong fluid.
People are correct in stating that NORMAL 2 wheel drive vehicles are not locked and have a differential to transfer power and prevent the axles from turning at the same speeds when turning.. when working properly..key words..when working properly.
P.S. This isn't aimed at anyone so please no one take this as a personal attack..its not.
While I'm at it..heres a pic of my 49 merc.Its a drag car..429cid powered by ford..set up to go straight and do it fast.Rear end has the spider gears welded for going straight..not street legal..wheels hop when loading on the trailer or turning sharp in the drive.I do have a bit of experience with cars.
Last edited by posttal; Nov 22, 2009 at 10:23 AM.
Suspended
Joined: Nov 2007
Posts: 6,657
Likes: 0
This thread really needs to be closed out.
The comments seem to be getting dumber and dumber..but said with such conviction.
I tried to explain this but some of the arm chair mechanics are like kids that just yell louder when there wrong.I know what your thinking,how would I know,after all I'm just a certified master tech for the past 23 that certaintly doesn't carry as much weight as lets say..a truck driver or CPA.
So..will someone PLEASE back up there statements with something other than here say.
I'm gonna put a link here..please read it.
http://www.denalitrucks.com/documents/TL_Jan03.pdf
I'm sure most mechanics are familiar with this and by no means am I trying to insult you.But some of these comment are so off the wall made by guys that own but don't know how to repair.
And before anyone starts flaming and yelling please back up what your saying with some facts...hard cold facts.Also why are we even at this point..the original question was pretty much answered long ago..with the bottom line being that its normal of 4 wheel drives on dry pavement to skip..why is besides the point..it happens.Can we please at least all agree on that ?
Oh and by the way..I'v raced cars for years and 2 rear wheel drive drag cars (1/4 mile cars)get wheel hop.(NOT ALL,BUT A LOT DEPENDING ON THE SET UP) The rear ends on many are locked giving power to both wheels..no slipage..and when moving off the trailer as most hot rodders will tell you they get wheel hope.And these are 2 wheel drive cars. ALSO in street cars limited slips diffs NEED an additve to aid in the slipage..if not present they will also lock up..and these are 2 wheel drive cars.Although rare..it does happen when backyard mechainics dont read the manual and ad the wrong fluid.
People are correct in stating that NORMAL 2 wheel drive vehicles are not locked and have a differential to transfer power and prevent the axles from turning at the same speeds when turning.. when working properly..key words..when working properly.
P.S. This isn't aimed at anyone so please no one take this as a personal attack..its not.
While I'm at it..heres a pic of my 49 merc.Its a drag car..429cid powered by ford..set up to go straight and do it fast.Rear end has the spider gears welded for going straight..not street legal..wheels hop when loading on the trailer or turning sharp in the drive.I do have a bit of experience with cars.
The comments seem to be getting dumber and dumber..but said with such conviction.
I tried to explain this but some of the arm chair mechanics are like kids that just yell louder when there wrong.I know what your thinking,how would I know,after all I'm just a certified master tech for the past 23 that certaintly doesn't carry as much weight as lets say..a truck driver or CPA.
So..will someone PLEASE back up there statements with something other than here say.
I'm gonna put a link here..please read it.
http://www.denalitrucks.com/documents/TL_Jan03.pdf
I'm sure most mechanics are familiar with this and by no means am I trying to insult you.But some of these comment are so off the wall made by guys that own but don't know how to repair.
And before anyone starts flaming and yelling please back up what your saying with some facts...hard cold facts.Also why are we even at this point..the original question was pretty much answered long ago..with the bottom line being that its normal of 4 wheel drives on dry pavement to skip..why is besides the point..it happens.Can we please at least all agree on that ?
Oh and by the way..I'v raced cars for years and 2 rear wheel drive drag cars (1/4 mile cars)get wheel hop.(NOT ALL,BUT A LOT DEPENDING ON THE SET UP) The rear ends on many are locked giving power to both wheels..no slipage..and when moving off the trailer as most hot rodders will tell you they get wheel hope.And these are 2 wheel drive cars. ALSO in street cars limited slips diffs NEED an additve to aid in the slipage..if not present they will also lock up..and these are 2 wheel drive cars.Although rare..it does happen when backyard mechainics dont read the manual and ad the wrong fluid.
People are correct in stating that NORMAL 2 wheel drive vehicles are not locked and have a differential to transfer power and prevent the axles from turning at the same speeds when turning.. when working properly..key words..when working properly.
P.S. This isn't aimed at anyone so please no one take this as a personal attack..its not.
While I'm at it..heres a pic of my 49 merc.Its a drag car..429cid powered by ford..set up to go straight and do it fast.Rear end has the spider gears welded for going straight..not street legal..wheels hop when loading on the trailer or turning sharp in the drive.I do have a bit of experience with cars.
OK
how about we stay on track and stick to the topic. this thread has nothing to do with racing, and what you stated was state on the 1st or second page IIRC.
Senior Member
Joined: Jul 2009
Posts: 219
Likes: 0
From: cleveland.ohio
I kinda agree..it has nothing to do with racing...but when some one stated that 2 wheel drive cars dont get wheel hop I felt I had to make the statement that this is untrue.And by going the route I did it kinda proved my point.Its just irritating when people make "blanket statements" and use words like "impossable" then other people take it as gospel and then post it and the myth goes on and on.Kinda like the sightings of bigfoot posted on the web.after all if its on the web it has to be true.
Instead use words like"in my opinion,sometimes,usually etc,etc"All I'm trying to say is that this thread has some truths and some misconceptions and people need to do some research.And NOT at other forums but at sites suppling you with information and not just more hearsay.I'v tried to at least show my way of thinking to prove..MY OPINION.
If you disagree with ANYONES opinion then lets not argue about it,lets discuss and learn from each other with some facts..After all you never stop learning.And as the wife is quick to point out I don't know everything.
Instead use words like"in my opinion,sometimes,usually etc,etc"All I'm trying to say is that this thread has some truths and some misconceptions and people need to do some research.And NOT at other forums but at sites suppling you with information and not just more hearsay.I'v tried to at least show my way of thinking to prove..MY OPINION.
If you disagree with ANYONES opinion then lets not argue about it,lets discuss and learn from each other with some facts..After all you never stop learning.And as the wife is quick to point out I don't know everything.
Technical Article Contributor
Joined: Nov 2002
Posts: 2,804
Likes: 9
From: Wisconsin
Please go back an read the question again, and then the entire post.
Yes I agree that if you weld the spider gears of an F150 the rear wheels will hop side to side. And some two rear wheel drive race cars have the rear axle locked, and they will wheel hop side to side when turning. And if an F150 wheels hop side to side then something is wrong with it's axle.
Here is a quote from Wikipedia.
"A four-wheel drive (4WD) vehicle will have at least two differentials (one in each axle for each pair of driven roadwheels), and possibly a centre differential to apportion torque between the front and rear axles. In some cases (eg. Lancia Delta Integrale, Porsche 964 Carrera 4 of 1989 [2]) the centre differential is an epicyclic differential (see below) to divide the torque asymmetrically, but at a fixed rate between the front and rear axle. Other methods utilise an 'Automatic Torque Biasing' (ATB) centre differential, such as a Torsen - which is what Audi use in their quattro cars (with longitudinal engines).
4WD vehicles without a centre differential should not be driven on dry, paved roads in four-wheel drive mode, as small differences in rotational speed between the front and rear wheels cause a torque to be applied across the transmission. This phenomenon is known as "wind-up", and can cause considerable damage to the transmission or drive train. On loose surfaces these differences are absorbed by the tire slippage on the road surface.
A transfer case may also incorporate a centre differential, allowing the drive shafts to spin at different speeds. This permits the four-wheel drive vehicle to drive on paved surfaces without experiencing "wind-up"."
Differential
Yes I agree that if you weld the spider gears of an F150 the rear wheels will hop side to side. And some two rear wheel drive race cars have the rear axle locked, and they will wheel hop side to side when turning. And if an F150 wheels hop side to side then something is wrong with it's axle.
Here is a quote from Wikipedia.
"A four-wheel drive (4WD) vehicle will have at least two differentials (one in each axle for each pair of driven roadwheels), and possibly a centre differential to apportion torque between the front and rear axles. In some cases (eg. Lancia Delta Integrale, Porsche 964 Carrera 4 of 1989 [2]) the centre differential is an epicyclic differential (see below) to divide the torque asymmetrically, but at a fixed rate between the front and rear axle. Other methods utilise an 'Automatic Torque Biasing' (ATB) centre differential, such as a Torsen - which is what Audi use in their quattro cars (with longitudinal engines).
4WD vehicles without a centre differential should not be driven on dry, paved roads in four-wheel drive mode, as small differences in rotational speed between the front and rear wheels cause a torque to be applied across the transmission. This phenomenon is known as "wind-up", and can cause considerable damage to the transmission or drive train. On loose surfaces these differences are absorbed by the tire slippage on the road surface.
A transfer case may also incorporate a centre differential, allowing the drive shafts to spin at different speeds. This permits the four-wheel drive vehicle to drive on paved surfaces without experiencing "wind-up"."
Differential
Senior Member
Joined: Jul 2009
Posts: 219
Likes: 0
From: cleveland.ohio
Wow ..now were quoting Wikipedia.
Ok,I read the above..is there a point here?Or are you refering to the line
If so its a very generic statemant as all Wikipedia statement are...and applies mainly to all wheel drive cars and has nothing to do with a F-150 as this site is based on.I thought All F-150 owners knew this because if it were true this acticle wouldn't have been written in the first place.WE all know you can't drive a 4x4 on hard dry surfaces and not experience a problem..hell it even says so right in ther service manual.So why are we still beating a dead horse here???
Please dont quote Wikipedia if you want to be taken seriously..If you click on the tab in the side bar in Wikipedia that says ABOUT wikipedia is says the following..
If your not sure and want to toss in someone elses quote thats fine but it should at least be from a service manual...an automotive site..a manufacturer..or in this case maybe a site dealing with transmissions and drive-trains.Not some BS site that anyone regardless of education and backround can add to.I at least have quoted sites dealing in the subject at hand....even the sperm whale comment I backed up if you follow the link.It seems people now are just searching the web to prove there point reguardless of the validity of the statements.
Again..theres pics of bigfoot on the web..that dont make it real.
Ok,I read the above..is there a point here?Or are you refering to the line
A transfer case may also incorporate a centre differential, allowing the drive shafts to spin at different speeds. This permits the four-wheel drive vehicle to drive on paved surfaces without experiencing "wind-up"."
Please dont quote Wikipedia if you want to be taken seriously..If you click on the tab in the side bar in Wikipedia that says ABOUT wikipedia is says the following..
Wikipedia (pronounced /ˌwiːkiˈpiːdi.ə/, WEE-kee-PEE-dee-ə or /ˌwɪkɨˈpiːdi.ə/, WI-ki-PEE-dee-ə) is a multilingual, Web-based, free-content encyclopedia project based mostly on anonymous contributions. The name "Wikipedia" is a portmanteau of the words wiki (a technology for creating collaborative websites, from the Hawaiian word wiki, meaning "quick") and encyclopedia. Wikipedia's articles provide links to guide the user to related pages with additional information.
Wikipedia is written collaboratively by an international group of volunteers. Anyone with internet access can write and make changes to Wikipedia articles. There are no requirements to provide one's real name when contributing; rather, each writer's privacy is protected unless they choose to reveal their identity themselves.
Wikipedia is written collaboratively by an international group of volunteers. Anyone with internet access can write and make changes to Wikipedia articles. There are no requirements to provide one's real name when contributing; rather, each writer's privacy is protected unless they choose to reveal their identity themselves.
Again..theres pics of bigfoot on the web..that dont make it real.
Last edited by posttal; Nov 24, 2009 at 07:56 AM.
when do i turn on my fog lights???
Senior Member
Joined: Dec 2008
Posts: 1,626
Likes: 0
From: Jackson, Georgia
the gear ratios are the same front and rear
why, whenever you are driving the truck of course, i mean duh...
why, whenever you are driving the truck of course, i mean duh...
Senior Member
Joined: Oct 2007
Posts: 546
Likes: 0
From: Georgetown, Canada
When there is wet leaves on the road.
Sorry I could not help myself. This post was a interesting and funny read. One dumb question and you scared for life on this forum.
Sorry I could not help myself. This post was a interesting and funny read. One dumb question and you scared for life on this forum.