4 wheel drive..., why?
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Joined: Nov 2002
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From: Wisconsin
Interesting that the question is still not answered. This happens because your rear wheels are turning slower and getting dragged by the front wheels. When you engage 4x4 the front axle and rear axle become locked together by the transfer case. When that happens the front wheels need to turn at the same speed as the rear wheels, (or the wheels need to be able to slip.) That is why all four tires need to be the exact same size.
When you make a turn the rear wheels make a smaller circle than the front wheels, leaving the front wheels spinning faster. Since the front and rear wheels are turning at different speeds while sharing the same drive train, either the slower wheels get dragged along, or the faster wheels slip in their attempt to drag the other two wheels along. Clearly dragging two wheels is going to slow the truck down and require more throttle. In addition, the drive train is binding up which may add some additional resistance.
This is true four wheel drive. It has nothing to do with the inside and outside wheels because they are separated by a universal in both 4x2 and 4x4 operation.
When you make a turn the rear wheels make a smaller circle than the front wheels, leaving the front wheels spinning faster. Since the front and rear wheels are turning at different speeds while sharing the same drive train, either the slower wheels get dragged along, or the faster wheels slip in their attempt to drag the other two wheels along. Clearly dragging two wheels is going to slow the truck down and require more throttle. In addition, the drive train is binding up which may add some additional resistance.
This is true four wheel drive. It has nothing to do with the inside and outside wheels because they are separated by a universal in both 4x2 and 4x4 operation.
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Joined: Oct 2007
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From: Ny
Interesting that the question is still not answered. This happens because your rear wheels are turning slower and getting dragged by the front wheels. When you engage 4x4 the front axle and rear axle become locked together by the transfer case. When that happens the front wheels need to turn at the same speed as the rear wheels, (or the wheels need to be able to slip.) That is why all four tires need to be the exact same size.
When you make a turn the rear wheels make a smaller circle than the front wheels, leaving the front wheels spinning faster. Since the front and rear wheels are turning at different speeds while sharing the same drive train, either the slower wheels get dragged along, or the faster wheels slip in their attempt to drag the other two wheels along. Clearly dragging two wheels is going to slow the truck down and require more throttle. In addition, the drive train is binding up which may add some additional resistance.
This is true four wheel drive. It has nothing to do with the inside and outside wheels because they are separated by a universal in both 4x2 and 4x4 operation.
When you make a turn the rear wheels make a smaller circle than the front wheels, leaving the front wheels spinning faster. Since the front and rear wheels are turning at different speeds while sharing the same drive train, either the slower wheels get dragged along, or the faster wheels slip in their attempt to drag the other two wheels along. Clearly dragging two wheels is going to slow the truck down and require more throttle. In addition, the drive train is binding up which may add some additional resistance.
This is true four wheel drive. It has nothing to do with the inside and outside wheels because they are separated by a universal in both 4x2 and 4x4 operation.
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Senior Member
Joined: Feb 2009
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Interesting that the question is still not answered. This happens because your rear wheels are turning slower and getting dragged by the front wheels. When you engage 4x4 the front axle and rear axle become locked together by the transfer case. When that happens the front wheels need to turn at the same speed as the rear wheels, (or the wheels need to be able to slip.) That is why all four tires need to be the exact same size.
When you make a turn the rear wheels make a smaller circle than the front wheels, leaving the front wheels spinning faster. Since the front and rear wheels are turning at different speeds while sharing the same drive train, either the slower wheels get dragged along, or the faster wheels slip in their attempt to drag the other two wheels along. Clearly dragging two wheels is going to slow the truck down and require more throttle. In addition, the drive train is binding up which may add some additional resistance.
This is true four wheel drive. It has nothing to do with the inside and outside wheels because they are separated by a universal in both 4x2 and 4x4 operation.
When you make a turn the rear wheels make a smaller circle than the front wheels, leaving the front wheels spinning faster. Since the front and rear wheels are turning at different speeds while sharing the same drive train, either the slower wheels get dragged along, or the faster wheels slip in their attempt to drag the other two wheels along. Clearly dragging two wheels is going to slow the truck down and require more throttle. In addition, the drive train is binding up which may add some additional resistance.
This is true four wheel drive. It has nothing to do with the inside and outside wheels because they are separated by a universal in both 4x2 and 4x4 operation.
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Joined: Apr 2005
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From: minnesota - ubetcha
4x4 hi isn't supposed to go above 45mph anyway. (I'd assume your around that if your on paving)
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Joined: Aug 2007
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From: Plymouth, Minnesota
"Move the 4WD control between 2H and 4Hat any forward speed up to 55MPH (88 KM/H)"
"Note: Do not perform this operation at speeds above 45MPH (72 KM/H) if the outside temperature is below 32 degrees F (0 degrees C)."
From the manual of my '05 Lariat. When the freeways are covered in ice, I drive in 4H (I've done 70MPH) to avoid my rear end spinning me loose from throttle application. I saw a guy last year in an SUV slam into the concrete wall right in front of me from too much throttle in 2H. Traffic had slowed down, as he went to speed back up...rear end slid out.
"Note: Do not perform this operation at speeds above 45MPH (72 KM/H) if the outside temperature is below 32 degrees F (0 degrees C)."
From the manual of my '05 Lariat. When the freeways are covered in ice, I drive in 4H (I've done 70MPH) to avoid my rear end spinning me loose from throttle application. I saw a guy last year in an SUV slam into the concrete wall right in front of me from too much throttle in 2H. Traffic had slowed down, as he went to speed back up...rear end slid out.
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Joined: Jul 2009
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From: cleveland.ohio
? I dont think so but its not worth quabbling about..but for the record the outside and inside diameter is different and when locked in 4x4 you are correct they are all spinning at the same rotation INCLUDING the left and right wheels causing the hard steering and wheel hop.I've never heard of a difference front to back that would cause wheel hop.Unless I skipped something here and we're talking about something else..in that case..sorry to butt in.
I have a 51 merc with a lock welded possi 2 wheel drive that is made to go straight and wheel hops the same when making a tight turn..with only as mentioned a 2 w.d rear end due to not having any slipage in the rear end.You can actually see the inside wheel skip or jump as I turn it in the drive when I put it in the trailer due to the inside tire trying to keep up with the outside tire.Its the same thing on 4x4's.Even my vette needed a special additive to aid in the slipage of in the rear end due to this.I bought it from a guy that thought the rear end was shot due to the "noise' it made when turning.I went up and bought the posi trac oil..which I was told was made with whale sperm..I kid you not..thats what GM said..whatever it has in it it aids in the slippage and the noise went away.
If still confused try this link http://auto.howstuffworks.com/four-wheel-drive2.htm its pretty basic auto 101 stuff but it explains it pretty good.
1 thing I think we all CAN agree on is that in a tight turn on dry pavement turn off the 4x4.
I have a 51 merc with a lock welded possi 2 wheel drive that is made to go straight and wheel hops the same when making a tight turn..with only as mentioned a 2 w.d rear end due to not having any slipage in the rear end.You can actually see the inside wheel skip or jump as I turn it in the drive when I put it in the trailer due to the inside tire trying to keep up with the outside tire.Its the same thing on 4x4's.Even my vette needed a special additive to aid in the slipage of in the rear end due to this.I bought it from a guy that thought the rear end was shot due to the "noise' it made when turning.I went up and bought the posi trac oil..which I was told was made with whale sperm..I kid you not..thats what GM said..whatever it has in it it aids in the slippage and the noise went away.
If still confused try this link http://auto.howstuffworks.com/four-wheel-drive2.htm its pretty basic auto 101 stuff but it explains it pretty good.
1 thing I think we all CAN agree on is that in a tight turn on dry pavement turn off the 4x4.
Last edited by posttal; Nov 14, 2009 at 06:07 PM.
Senior Member
Joined: Jul 2007
Posts: 487
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From: WA
I have also had my truck up to 65-70 in 4wd on the highway with no problem. When on a road with slush/ice/light powder, it helps greatly to reduce the risk of having the *** end swing out on you with throttle like mentioned above.
If you do encounter patches of sanded, snow free road, you are still good as long as you are keeping the wheel straight (easy on open highway).
If you do encounter patches of sanded, snow free road, you are still good as long as you are keeping the wheel straight (easy on open highway).
Suspended
Joined: Nov 2007
Posts: 6,657
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? I dont think so but its not worth quabbling about..but for the record the outside and inside diameter is different and when locked in 4x4 you are correct they are all spinning at the same rotation INCLUDING the left and right wheels causing the hard steering and wheel hop.I've never heard of a difference front to back that would cause wheel hop.Unless I skipped something here and we're talking about something else..in that case..sorry to butt in.
I have a 51 merc with a lock welded possi 2 wheel drive that is made to go straight and wheel hops the same when making a tight turn..with only as mentioned a 2 w.d rear end due to not having any slipage in the rear end.You can actually see the inside wheel skip or jump as I turn it in the drive when I put it in the trailer due to the inside tire trying to keep up with the outside tire.Its the same thing on 4x4's.Even my vette needed a special additive to aid in the slipage of in the rear end due to this.I bought it from a guy that thought the rear end was shot due to the "noise' it made when turning.I went up and bought the posi trac oil..which I was told was made with whale sperm..I kid you not..thats what GM said..whatever it has in it it aids in the slippage and the noise went away.
If still confused try this link http://auto.howstuffworks.com/four-wheel-drive2.htm its pretty basic auto 101 stuff but it explains it pretty good.
1 thing I think we all CAN agree on is that in a tight turn on dry pavement turn off the 4x4.
I have a 51 merc with a lock welded possi 2 wheel drive that is made to go straight and wheel hops the same when making a tight turn..with only as mentioned a 2 w.d rear end due to not having any slipage in the rear end.You can actually see the inside wheel skip or jump as I turn it in the drive when I put it in the trailer due to the inside tire trying to keep up with the outside tire.Its the same thing on 4x4's.Even my vette needed a special additive to aid in the slipage of in the rear end due to this.I bought it from a guy that thought the rear end was shot due to the "noise' it made when turning.I went up and bought the posi trac oil..which I was told was made with whale sperm..I kid you not..thats what GM said..whatever it has in it it aids in the slippage and the noise went away.
If still confused try this link http://auto.howstuffworks.com/four-wheel-drive2.htm its pretty basic auto 101 stuff but it explains it pretty good.
1 thing I think we all CAN agree on is that in a tight turn on dry pavement turn off the 4x4.
what i think you said to an extent and round about way is the inner tire and outter tire in a turn go different distances which causes binding causing the chirping. in 2wd you dont really notice it because the LS disengages or you just dont have LS so only one wheel spins. thats why if you have a locked rear end it chirps around turns.
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From: cleveland.ohio
Sorry if I'm typing too fast
But you seemed to grasp the jist of it.
The ORIGINAL question concerning turning on dry pavement in 4x4 is caused by as I said above..the diameter of the turning radius of the inside and outside tire being DIFFERENT and when locked in 4x4 you get hoping,skiping and as you called it.. chirping.. along with the hard steering since the wheels are forced to spin at the same rotation when locked in 4x4..unlike there ability to have limited slipage when in 2 wheel dr allowing the inner wheel to turn slower..It has nothing to do with the front and rear speeds being different...but the side to side rotation.
I threw in an example since you get the same skipping on a 2 wheel drive vehicle IF its a locked possi or has defective possi rear end..or as in my case no additve in the rear end to allow for smooth slipage..People seemed to be getting way off track..thought I'd do the same and beat around the bush to answer a simple question.The rest were just examples explaining the point since theres alway someone that disagrees.Its been a rough day and I felt like haveing a few drinks and typing a bit to unwind.but also didn't feel like arguing so I tossed in a few reference points.Sorry if I oversteped any forum boundaries...
But you seemed to grasp the jist of it.
The ORIGINAL question concerning turning on dry pavement in 4x4 is caused by as I said above..the diameter of the turning radius of the inside and outside tire being DIFFERENT and when locked in 4x4 you get hoping,skiping and as you called it.. chirping.. along with the hard steering since the wheels are forced to spin at the same rotation when locked in 4x4..unlike there ability to have limited slipage when in 2 wheel dr allowing the inner wheel to turn slower..It has nothing to do with the front and rear speeds being different...but the side to side rotation.
I threw in an example since you get the same skipping on a 2 wheel drive vehicle IF its a locked possi or has defective possi rear end..or as in my case no additve in the rear end to allow for smooth slipage..People seemed to be getting way off track..thought I'd do the same and beat around the bush to answer a simple question.The rest were just examples explaining the point since theres alway someone that disagrees.Its been a rough day and I felt like haveing a few drinks and typing a bit to unwind.but also didn't feel like arguing so I tossed in a few reference points.Sorry if I oversteped any forum boundaries...
Last edited by posttal; Nov 15, 2009 at 12:47 AM.
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Joined: Jul 2009
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From: cleveland.ohio
Well..that was my mistake..and an honest one at that now that I did a little research this morning.
I WRONGLY stated that Gm rear end additive is made from whale sperm..I was told this a few years back by a parts guy at a local dealership when buying a rear differential additive that is needed to prevent rear wheel hop in my 78 vette.The rear rear hop and wheel skip is related to this posting and I thought it was relivent.
BUT..in doing some checking this morning I found that the additive was actually made from SPERM WHALE oil..NOT WHALE SPERM.Keep in mind I said above that this was what I was told by a guy at GM..didnt know if was fact or urban myth.ALSO before anyone jumps down my throat the Endangered Species Act outlaw the use of sperm whale oil back in the 70's so unless the stuff the guy sold me was an very old bottle he was wrong again.Sperm whale additves WERE needed to prevent wheel hop and friction breakdown in GM vehicles but replaced with synthetic oils.My car being a 78 was caught in the middle and the guy before me changed gear lube and put in no additives..
NOW back to FORDS ..ford also recommend an additive in there differentials..ford LSD fiction modifier OR use a synthetic gear lube like Mobil 1 Synthetic Gear Lube LS 75W-90 ..the LS standing for Limited Slip.
So back to the ORIGINAL question of this posting..you should also be sure your running the proper gear lube if you bought the truck used.Although running on dry pavement in 4wd will cause wheel chatter and I'm sure thats your original problem ..its no big deal...but so will not having the proper lube in the differential.
Oh and below is a link to the sperm whale stuff..
http://www.lubegard.com/LXE.aspx
And heres a link to THIS forum discussing this additive..
https://www.f150online.com/forums/ot...rear-diff.html
Sorry for ant miss information..as I stated..it was a rum and coke night after having to put my dog of 16 yrs down and I was rambling and making little sense..as I'm sure i am now.
I WRONGLY stated that Gm rear end additive is made from whale sperm..I was told this a few years back by a parts guy at a local dealership when buying a rear differential additive that is needed to prevent rear wheel hop in my 78 vette.The rear rear hop and wheel skip is related to this posting and I thought it was relivent.
BUT..in doing some checking this morning I found that the additive was actually made from SPERM WHALE oil..NOT WHALE SPERM.Keep in mind I said above that this was what I was told by a guy at GM..didnt know if was fact or urban myth.ALSO before anyone jumps down my throat the Endangered Species Act outlaw the use of sperm whale oil back in the 70's so unless the stuff the guy sold me was an very old bottle he was wrong again.Sperm whale additves WERE needed to prevent wheel hop and friction breakdown in GM vehicles but replaced with synthetic oils.My car being a 78 was caught in the middle and the guy before me changed gear lube and put in no additives..
NOW back to FORDS ..ford also recommend an additive in there differentials..ford LSD fiction modifier OR use a synthetic gear lube like Mobil 1 Synthetic Gear Lube LS 75W-90 ..the LS standing for Limited Slip.
So back to the ORIGINAL question of this posting..you should also be sure your running the proper gear lube if you bought the truck used.Although running on dry pavement in 4wd will cause wheel chatter and I'm sure thats your original problem ..its no big deal...but so will not having the proper lube in the differential.
Oh and below is a link to the sperm whale stuff..
http://www.lubegard.com/LXE.aspx
And heres a link to THIS forum discussing this additive..
https://www.f150online.com/forums/ot...rear-diff.html
Sorry for ant miss information..as I stated..it was a rum and coke night after having to put my dog of 16 yrs down and I was rambling and making little sense..as I'm sure i am now.
Last edited by posttal; Nov 15, 2009 at 02:40 PM.
