4WD low is a no go

[PaulD]

Cannot get my 89 GW into 4WD Lo. Yes - I am in 4WD and in/out of Hi is no problem but will not go into Lo. If I am in neutral, and shift to Lo, it feels like it engages but when I try to move, nothing happens and if I try to engage while in gear (not moving), I get a lot of gear grinding. I can engage while in neutral and then hold the Hi/Lo shifter firmly in Lo with my hand then shift to drive, nothing happens but if I pull harder on the Hi/Lo lever, I get gear grind. When I am in neutral and shift into Lo, it feels like it has engaged but obviously something is not right.
Any trick to this process I am missing or is this an indication of a xfer case problem? Is it actually engaging while in neutral and then jumping out of gear when I shift to drive? If so, what would cause that?

[will e]

The np229 is not a case I am familiar with. Reading your attempts I did not see "While moving slowly (2mph or so) with the transmission in Neutral"

This is pretty typical for getting into 'low'.

[PaulD]

I knew I need to be moving to shift between 2WD and 4WD but I neglected to see the 2-3mph for shifting into Lo in the owners manual. Seems strange that the proper procedure is to shift into Lo at 2-3 MPH while the transmission is in neutral. Guess I need to be rolling downhill or have some guys pushing me????
Will give it a try later today after the current rain storm passes through.

[tgreese]

Neutral is pretty much your only choice other than park. With an automatic, if the transmission is in gear, the engine will over-run the drive train and you won't be able to slide into low range without a lot of gear clash, if at all.

Shifting from 2wd high to 4WD high and back keeps the front and rear driveshafts turning together, since they are connected together through contact with the ground. So even if you disconnect the front from the rear, the axles will both turn at the same speed.

Typically it's ok to drop into neutral and shift from low to high and back at a very low speed ... a baby crawl. Idle along and slip into neutral. Then as you approach a stop, slide into low range. Try it in the parking lot to get the hang of it. It's ok to try and shift to low range when in park, but then the gears will be stationary and they may not line up, and block you from shifting. A tiny bit of forward movement helps the gears to find an alignment and slip together. (Really, I think there's a lock plate in the NP transfer cases that has to line up, not gears, but the effect is the same).

hth!

[will e]

What I have found to be an effective strategy for shifting into/out of low is to do it on hills. I stop the truck, put it in Neutral, take my foot off the brake and as I start to roll I shift. This is handy so that if you 'miss' and end up in neutral you can stop the truck, let it start running again, and try again.

Many people will simply slow down, put the truck in neutral and attempt the shift. If you are on flat ground, you miss the shift and you stop rolling it is a dice roll if you will get it into a gear or not. All of this varies with TC type. If you find yourself stopped and with the TC in neutral the best bet is to turn the engine off and leave the transmission in neutral and see if you can get it to go in.

[PaulD]

Tried all your suggested tricks and no dice so far. When I shift into Lo and transmission is in park or neutral, I get nice thump like it is going into Lo gear but when I shift to drive, it acts like xfer is in neutral then when I try to push it into Lo, I get the gear clash. Does xfer case have a easily recognizable neutral position. Am I shifting in neutral and thinking I am in Lo and not going all the way into Lo?

[BCRAWLER]

Suggest crawling underneath and verifying slop in your linkage. Is there a body lift that may have changed the activation of low. Also maybe try blocking the wheels and disconnecting the shifter at the transfer case and see if you can put it in manually.

[will e]

On my NP208 it was a fair amount of movement for the flag shifter. Probably 4 or 5 inches. But it had 2wd, 4 high, N and 4 low. I suspect the 229 doesn't have to move as far. But that's a guess.

[PaulD]

Going underneath to check out potential linkage problem is my next step.

[Nikkormat]

it has a neutral position. As other have said make sure you are moving ever so slightly to make the shift easier. Also ensure that you are actually in 4wd. The light on the dash comes on right? Also check the fluid level the NP cases are known to get "sticky" going in and out of low range when the fluid is low or dirty.

For what it's worth when i first got my current GW I don't think low range had EVER been used. The linkage was not together correctly and it was coated in years of undisturbed dirt and grime. The first time I used low range in it was very difficult. I had to futz with it for a good couple of minutes to get it to slide in. But once I started using it regularly it got easier and easier to shift. I can shift it while stationary now.

I have also driven a few NP equipped vehicle that had low range blown clean out of them from abuse. They would shift into the low range position but violently pop out of gear once the transmission was placed back in gear. In most instances the case would grind like crazy when it popped out of gear. But in an XJ I test drove for a friend the case would simply pop back into neutral. Keep your hand on the shifter as you are testing and see what you feel.

[PaulD]

I doubt my GW has ever been in Lo in its entire life of 150,000 miles. I can shift into Lo (feels like it) and hold it in place with my hand while I slip into drive and nothing happens unless I pull really hard then I get the gear clash. I suspect you are right that the linkage is covered in crud or so tight that is not really going into Lo when I first shift it. Will get under it today and see what it looks like.

[will e]

So what happens if you pull really hard while moving slow and in neutral?

[PaulD]

Checked linkage and that should not be an issue. Clean with no obstructions. However, I finally got it to partially work in Lo. After pulling really hard and holding lever then shifting into drive, it will move forward. However, if I shift into reverse, it acts same as before with gear grind. Shift back to drive and it will move. Earlier it was suggested my fluid level may be low. Service manual also says a shifting problem may be due to low fluid. Not sure I understand why but I will pull the plug and top off my fluid. Uses Mopar Mercon or Dexron II auto xmission fluid. Don't have any on hand. Headed to store for some.

[rocklaurence]

Yeh, the 229 is finiky. I have the Twin stick setup for mine and I've found that you have to have the front axle engaged [if you have manual hubs] and you need to be rolling in most cases to shift. Also, there is an internal lock that wont allow Low unless its in 4WD. I've also had sucess by turning off the engine and shifting.

[PaulD]

Think I found problem. Pulled the fill plug and no drip - needs fluid. So I decided to take this opportunity to drain and refill so I pulled the drain plug and got about 1 pint of fluid out. Book says it hold 6 pints. Obviously a problem here. I will refill with the required 6 pints and hopefully be able to shift into Lo. Not sure I understand why low fluid would prevent shifting.

[will e]

You might be on to something. The parts do need a bit of grease to slip in and out.
My Atlas doens't like to go in and out of high/low when it is cold. So I am hopeful you have found the problem. Even if you haven't you may have just saved yourself an expensive repair!

Get a little hand pump, much easier than trying to use gravity.

[PaulD]

Got it filled up but had to rig up a pump (OSHA would have a fit). No room for a gravity flow. Now shifts into Lo/Drive much better but Lo/reverse sill a gear grind. I got it into Lo/reverse one time but only once. I think I will give the new fluid some time to work and it may loosen things up a bit. Hopefully if I can get it working a bit and do a lot of shifting between Hi/Lo the whole setup will loosen up enough to work right with no problem.

[will e]

Cool. But I don't completly understand your post. You are saying that you can get into LOW and Drive (forward) and it seems to work but if you put the transmission into reverse it just grinds?

[az chip]

I hope he is not trying to engage in 4 lo while putting it in reverse.

[PaulD]

I can put transmission in neutral then shift into Lo then shift into drive and it works going forward but if I then shift into reverse, nothing happens. Does not make sense to me. If it is in Lo for forward I would expect it to be in Lo for reverse. I shifted into Lo while sitting still. I need to try a slow roll shift into Lo as noted in owner manual. Have not tried that yet.