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4WD low works but no 4WD high

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When I pull back on the 4WD selector lever to go into 4WD high there isn't any real tension and it does not engage into 4WD. It feels loose or sloopy. When I pull the lever back all of the way, to go into 4WD low it does engage. FYI, There is plenty of tension when pulling it into low and you can feel it lock in. Also when going into low the light on the dash does activate. I know that not everyone on here believes in the lights ability to tell when it's in 4WD but I believe this one tobe accurate.

Has anyone had a similar problem with a fix?



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What your describing is kind of normal, you can shift between 2wd and 4hi "on the fly" up to about 30mph. It should be a smooth transaction.


When you shift into 4lo, you need to stop, and then shift into low, that's why you need to move the lever to the right to get pass the dog in the shifter, into neutral, then 4lo.


Shifting into 4hi is just engaging the chain in the TC.


Shifting into 4lo is also shifting the gear ratio in the TC.


You could very well be in 4w hi and not know it, do this on gravel, or dirt, not on hard pavement, but shift in 4hi, and hit the gas, see if you have spin on the front wheels.


Also.......after you shift out of 4lo, you should back up about 10 feet to disengage the TC.


Don't rely on the dash light, I had one that the light was on all the time, 2wd or 4wd, the switch was messed up, the pulling the wire off the switch solved that.


I've spent enough time in mine, that I can feel when it's in 4hi.

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Answer to the first reply... Yes I am sure that I am in 4 lo. The speed and whine of the engine is consistent with that of being in 4 lo.


As far as being in 4 hi, I am almost 100% sure that it is not engaging into 4 hi when pulling back on the lever. I use to drive a 95 YJ, so I am familiar with shifting on the fly, but I attempted to shift it into 4 hi at a stand still. There isn't any real tension, or pop, at that last second of pull when you pull back to go into 4 hi. Also the lever is almost at a 45 degree angle (or higher) when I pull the lever back. Like I said there isn't any real tension when pulling back to go into hi. It feels like it isn't even hooked up until I go past neutral to get it into lo range.

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It is powering the front in 4 lo? You verified this?


It's sounding to me like the vacuum switch for the CAD is screwed up... assuming of course, you're still running the CAD. Best fix is to lock it over and forget it's there.

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I am pretty sure that the front is being powered, I got in a predicament that I probably would not have been able to get out of if 4 lo wasn't working. FYI... I wasn't able to get out of the situation until going into 4lo.

I am still running the CAD. I got the truck from the 2nd owner who bought the truck when it was 2 years old. She is a friend of the family....and didn't do much driving let alone using 4 WD.

I have seen the thread on the CAD locking. I like the idea of the 4WD lights working like they are suppose to but understand at the same time who cares about the light if you know your in 4WD.


What does the CAD actually do?

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Here is how I test for proper transfercase operation (engagement only):


Let the truck idle and in 2wd


get under the truck and spin the front driveshaft by hand (it should be free and with little resistance)


shift into 4wd


get back under the truck and try and spin the driveshaft (a working shifter/selector will "lock" the driveshaft from free spinning)


I hope this helps, I actually did this on the trail to diagnose my issues before.

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If you've got a CAD, I would do this:

-turn on the truck (engine should be on for this test to assure vacuum is available for CAD operation),

-shift into 4wd high,

-drive like 20 feet just to be sure everything has moved into place (t-case and CAD collar),

-block a tire and put truck in park if auto or shift into neutral for manuals,

-jack up front/passenger side tire and try to spin it.


If the CAD and t-case work properly, then that front tire shouldn't spin. If it moves, then try to rotate the front driveshaft. If the t-case works properly, then the front driveshaft won't move.

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I havn't had the time to check out the CAD yet, but I still think, feel that's it's in the linkage. I still plan on checking it with your suggestion.

I just can't get my head around why there isn't any tension what so ever when I pull the lever back. I'm convinced that it's loose or something fell off from the bottom. I've looked at the linkage on underneath and it looks like its rubbing a little bit on the underside of the hump. Got to get it up on a lift.

I'll let you know.

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Well... I guess I really won't know until I check the CAD as recommended. FYI when I say no tension I mean none. There is also no click...when I say click I mean that last lil bit, .25in as you are actually engaging the 4WD. It's slack all the way back to the neutral position.

Ughhh... I'll get er figured out......later as opposed to sooner.

She drives great as a grocery getter though!

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well, don't see how there could be no resistance moving the lever to 4high, but resistance and engagement with 4low if it were an external linkage issue. does it bind and jump turning in 4low, or do you know it is 4low just by engine rpm? could be an internal problem with the case where range fork is moving, but mode fork is not, and you are just getting 2low but not engaging the front output, which would still reduce overall ratio and cause high rpm's at speed like 4low.

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If you are checking from under the truck and can turn the driveline by hand after shifting into 4 hi, then it means you need to adjust your shift linkage. You aren't engaging the transfercase completely into 4 wheel drive... Plain and simple... Old, soft transmission and motor mounts can cause that...

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