ZUKIWORLD Online | Suzuki 4x4 Editorial and Forum
ZUKIWORLD Discussion Forum => Technical Discussion - Beginner / Repair => Topic started by: frenchy065 on October 28, 2010, 02:38:47 PM
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Can anyone tell me what may be wrong and what the fix might be if i have my zuk in four high and when i hit about 30 mph it pops into two high
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Are you driving it on dry pavement in 4-high???
If you are, it's your transfer case tellin' you to STOP THAT!
You should NEVER drive any part-time 4x4 on dry pavement in any 4x4 mode! All the Suzuki SUVs and GM-badged equivalents have part-time 4x4 drivetrains.
Alternatively, you shifter sheet may on it's last legs...
For more info on what a shifter sheet is, do a search for those words at Ack's FAQ. The link is in my signature...
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Not sure I follow you ACK... Why should you not drive a 4x4 on the street in 4wd high ???
I have had a few different 4x4 vehicles and the manual usually states that a person should not drive above "X" mph in 4wd LOW and "X" mph in 4wd HIGH. But none of them stated that it should not be driven in 4wd on dry pavement.
Obviously these other vehicles were not a Sami (not sure if I have my Sami manual) but I have driven my Sami the same way. Every once in awhile I have thrown mine into 4wd and give it a mile or two of 4wd on the pavement. Of course, I don't switch on the lockers on the dry pavement.
Not trying to contradict you ( you are extremely knowledgable) but rather just trying to learn why....
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excellent question, my996duc1.
When you drive on dry pavement in the 4x4 mode all four wheels generally are getting excellent pavement traction. There is nothing - like water, wet road oils or loose gravel - that will allow the tire to slip on the pavement.
Because part-time 4x4 systems do not have a central differential or a viscus coupling like AWD vehicles do, differences in the rotational speed (RPMS) between the front axle and rear axle - caused by steering actions, tire wear or uneven inflation - creates torsional stress (called winding) in the differentials, driveshafts and transfer case gearing. When the winding stress builds up there is nothing in the drivetrain that can cause the winding stress to relieve itself.
As a result, something has to give at a weak point in the system. The result - at the least - is that a tire might break traction or the transfer case pops out of the 4x4 mode from the internal winding stress buildup. If you have tight fitting shift linkages, the stress might shear off a few teeth somewhere.
To further illustrate this, the British Army was using an amphibious 6x6 5-ton truck during the cold war called the Alvis Stalwart. The Alvis Stalwart had ONE differential driving the left and right set of wheels independently. This arrangement - which is worse that your Zuk's two differentials - went through hubs and gearboxes like poop through a goose! It got so bad that a service builletin was issued suggesting that, when driven any distance on dry pavement, the driver was supposed to regularly stop and drive over a curb to release the winding!
In conclusion:
Part-time 4wd on dry, smooth surfaces - BAD!
Part-time 4wd on slippery, rough surfaces GOOD!
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sweet. thanks for the explanation. makes sense now.
No more running the street in 4wd for me.
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You should NEVER drive any part-time 4x4 on dry pavement in any 4x4 mode! All the Suzuki SUVs and GM-badged equivalents have part-time 4x4 drivetrains.
Just so that you're aware - later model Grand Vitara (06 & later) are actually full time 4WD.
There are two versions, the base model and full time 4WD and four mode 4WD, which offers 4Hi, 4Hi locked, neutral and 4Lo locked - the locked of course refers to the center differential.
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well pointed out, fordem!
Newer Suzuki SUVs do offer AWD. Because AWD are full-time systems, they do not have winding problems.
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Its on dirt roads when i hit about 30 MPG
Are you driving it on dry pavement in 4-high???
If you are, it's your transfer case tellin' you to STOP THAT!
You should NEVER drive any part-time 4x4 on dry pavement in any 4x4 mode! All the Suzuki SUVs and GM-badged equivalents have part-time 4x4 drivetrains.
Alternatively, you shifter sheet may on it's last legs...
For more info on what a shifter sheet is, do a search for those words at Ack's FAQ. The link is in my signature...
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is the shifter sheet difficult to change out?
Are you driving it on dry pavement in 4-high???
If you are, it's your transfer case tellin' you to STOP THAT!
You should NEVER drive any part-time 4x4 on dry pavement in any 4x4 mode! All the Suzuki SUVs and GM-badged equivalents have part-time 4x4 drivetrains.
Alternatively, you shifter sheet may on it's last legs...
For more info on what a shifter sheet is, do a search for those words at Ack's FAQ. The link is in my signature...
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Hey...just want to thank you for the advise....i checked out the article on the shifter sheet. i will see if that does the trick.
thanks again