[Dustin07]

Hey Folks,

wasn't sure if this was the right place to post... but I have a question about using the 4wd on the 89 YJ I have... It's a manual tranny.

Is it OK (or is it recommended?) that you shift in and out of 4h/2wd while moving? if so, what are the optimum speeds? (like 2mph, 20mph, etc?).

also, when in 4wd, whats the max speed you suggest? what's the max speed when in 4h to kick it back down to 2wd? I'm driving on ice mostly, but how much of a beating can it take if I leave it in 4h on bare spots?


Reason I ask is because we've been uber spoiled with the super easy setup of the '02 Liberty and I just don't want to screw up the "new" 89 we just bought from the father-in-law the first week I have it.

tia

[drexelsteve]

I shift "on the fly" in my 89, never had a problem. Whenever i did that it was usually inbetween gearshift (trans in neutral). I always shift into low at a stop in neutral. As for top speeds etc... use your judgment. If you can do 50+, do you really need it in 4x4? I wouldn't worry too much about bare spots either, won't hurt it.

[Dustin07]

The liberty is always shifted in and out on the fly, and after reading the manuals on trucks of friends and family, I find that most vehicles seem to be this way (although everyone seems to think they need to be stopped! silly really, because it goes in and out easier on the fly). I just wanted to verify that other people are doing this before I wreck it since I don't have a manual yet for this rig.

I was thinking like if I'm doing 25mph in 2wd, can I push in the clutch and shift to 4h? Or do you think you really need to come out of gear?

and as far as max speed, I typically limit it to about 40-45 in fulltime on the liberty, this is while crossing the passes and whatnot snowboarding. but in the YJ I can't see myself doing more than 30-35 in 4wd. She just whines a bit more audibly in 4wd so I wanted to see what the 'norm' is.

thanks for your feedback

[learfxr]

I'm new to all 4x4's, but some transfer cases are built with synchros like a manual transmission is, some aren't. I tried to shift my 82 J-10 while rolling and it started to grind, so I always did it at a full stop from then on. I have the same style trans case in my YJ now (NP208) so I don't want to shift on the go with mine. Maybe I'm overly cautious, but I'm hell on transmissions and things like that. I always seem to tear them up.

[Richmond88yj]

The manual and common practice here is yes, up to 30.

However most do it under 5 mph.

[Big-n-Broke-YJ]

shifting on the fly is scary business.

why would you ever need to do this?


is it bc you are driving in snowy or possibly icey conditions or because you're wheeling in 2wd and start slipping or see a hairy spot in the trail coming up?

[ElvisV04290]

I shift on the fly on my auto 90 yj. I let of the gas and just pop the shifter back, then ease back on the gas and away I go. I pull a snowmobile trailer for a friend about once every two weeks, and there is always a tricky spot going up a steep dirt incline, I lock it in 4WD and then just disengage once I'm past it. So for me it was scary the first time since I don't know if I would get into 4WD or my transfer case would fall out from under the jeep. As for top speed and shift on the fly to four wheel drive? the manual says you can shift and travel in 4WD at "any legal speed", but why would you do 75 in 4x4 anyway.

[Big-n-Broke-YJ]

well that makes sense. i wonder if there is a difference in auto and 5 speed in terms of shifting the tc. i would assume not since they share the same tc.... oh well. good info for everyone...

[Mumachog]

Quoting from 93 jeep wrangler owners manual,
"4H Position:
This position is designed for temporary use of 4-wheel drive for traction when driving in rain, snow,mud,sand or when driving off road. Do not use 4H on dry paved roads. To engage, shift the transfer case lever from 2H to 4H while the vehicle is moving at any legal speed."

(personally i push in the clutch to shift it and i would be uncomfortable shifting it any faster than 25-30mph)

"4L Position:
This position is designed for temporary use of 4-wheel drive when off-road drivinng conditions require added low speed pulling power. Do not use 4L on dry paved roads. To engage, slow the vehicle to 2-3mph, shift the transmission to nuetral, then shift the transfer case lever to the right and pull firmly rearward to 4L.

CAUTION: Never attempt to engage Low range when vehicle is moving faster than 2-3 mph. Transfercase damage may result.

WARNING: Failure to engage a position completely can cause transfer damage or loss of power and vehicle control."

(usually when I need 4L i am stopped anyway so you can engage it when you are stopped and I wouldn't go any fster than say 10-15 mph in 4L)


long post, I was bored, hope this helps.

[absolut jeep]

I wouldn't worry about shifting on the fly if you're going 20 or so into 4hi. 4lo you should always be just about stopped in neutral.
Bare spots in between ice and snow drifts aren't going to hurt anything in 4hi, as long as there is less bare spots than covered spots.