PDA

View Full Version : Leave in 4H or take it in/out as needed?


PUNISHER VETTE
December 27th, 2009, 14:37
So we got a couple of inches of snow overnight.

Most of the main roads are drivable without needing 4H. But once you turn off those roads it gets a little rough.

Just didn't know what's harder on the car. Keeping it in 4H while running around town. Or engaging and disengaging it as i need it on the fly?

Matthew Currie
December 27th, 2009, 15:20
I engage/disengage. It should have no ill effect as long as everything is working correctly and you're not spinning any wheels.

Andy Steiner
December 27th, 2009, 19:10
So we got a couple of inches of snow overnight.

Most of the main roads are drivable without needing 4H. But once you turn off those roads it gets a little rough.

Just didn't know what's harder on the car. Keeping it in 4H while running around town. Or engaging and disengaging it as i need it on the fly?

Never EVER drive in four wheel drive while on pavement. EVER. You risk grenading your transfer case while in 4wd while driving on a hard surface. OTOH, if your rig has the NP242 transfer case you can safely drive in FULL TIME 4wd on all surfaces.

RidgeRunnerXJ
December 27th, 2009, 19:12
^^^^^^ What he said! Unless you have the 242 t-case with full time 4x4.

Begster
December 27th, 2009, 19:41
Just didn't know what's harder on the car. Keeping it in 4H while running around town. Or engaging and disengaging it as i need it on the fly?
It is a lot harder on the drive train when you are driving on a surface with high traction in 4wd. The transfercase was designed to be able to switch between 2 and 4, that is why it has a lever. The car was not designed to drive in 4wd around town, which is why it has 2wd.

WB9YZU
December 27th, 2009, 19:53
The fellow may not know the jargon guys.

If your 4WD shift lever goes:

2H, 4H, N, 4Lo

You have a Part Time transfer case. In other words, it is meant to be used part of the time.

Part time 4WD creates a hard connection between the front and rear axles, which allows you more traction for power. It is meant to be used only some of the time.

Full Time 4WD has a differential built into the transmission ( actually transfer case) which allows the front an rear axles to operate at different speeds. This system can be used all the time.

Note: No 4WD system improves braking times! Your 4WD vehicle will take just as long to stop as a 2WD vehicle on the same surface! Remember that when you fly past the other vehicles because you can go faster :D

My vehicle has Part Time 4WD, the shift pattern above.
I only use the 4H or 4Lo settings when the traction is marginal, or when off-road.
I do not use 4H on pavement when it is raining, or on Ice.
Rain generally has too much traction for the use of part time 4WD on pavement. If you use 4WD on ice, you could loose control while braking because the two axles are locked together and when one wheel stops, they tend to all lock up.

Hope that helps!

Ron

RidgeRunnerXJ
December 27th, 2009, 20:00
The fellow may not know the jargon guys.

True, thanks for explaining it.

kastein
December 27th, 2009, 22:58
I engage/disengage. It should have no ill effect as long as everything is working correctly and you're not spinning any wheels.
Took the words right out of my mouth. You can switch into 4Hi (either part time or full time) anytime you want to on slippery surfaces requiring it... as long as you aren't spinning wheels. So go easy on the skinny pedal (or coast) while shifting the transfer case and you'll be just fine.