Shifting in and out of 4wd speed?

[Prowelder]

What's up gang? I've got a simple question for you. What is the maximum reccomended speed for shifting in and out of 4wd? We recently got snow here and some of the roads are covered and some are dry so it's kinda a pita to stop and shift in and out as needed.

[Rogan]

2WD to 4WD-HI should not be an issue at normal speeds. I've done it at 30-35 before (several times) with no odd noises, grinding, jerking, etc.. Just like buttah.. This is with both my '96 and my '01..This may not be 'recommended', but I've done it/do it with no ill effects.

[Prowelder]

2WD to 4WD-HI should not be an issue at normal speeds. I've done it at 30-35 before (several times) with no odd noises, grinding, jerking, etc.. Just like buttah.. This is with both my '96 and my '01.. This may not be 'recommended', but I've done it/do it with no ill effects.

[Rogan]

given the fact that it's all interconnected, just disengaged, I don't see where 2H to 4H would cause any issues, to be honest. Having rebuilt several 231/241 tcases, they're quite simplistic in interior design. you're just moving a coupler. 4L, however, is a whole different creature. you're then engaging planetaries. (231 series has 3 planetary gears, whereas the 241 series has 6.)

[Heavyd1980]

highway speeds should still be ok since the t-case has plantary gears which act similar to synchros. but the slower speed is always a good safe choice.

[ISX]

The main thing is to just let off the pedal when you do it, you can't have the engine loading the drivetrain. I have put my ford in and out at 60mph, smooth as silk. There is a bigger discussion about this in an earlier thread. /threads/3295-4wd">http://forum.mopar1973man.com/threads/3295-4wd

[guesswho512]

several people over the years have told me that 2HI -> 4HI or 4HI->2HI should be done at less than 45mph

[Rogan]

highway speeds should still be ok since the t-case has plantary gears which act similar to synchros. but the slower speed is always a good safe choice.

[Prowelder]

Yeah I wasn't so worried about the transfer case as I've helped rebuild about three or four of them and don't see a problem with it. It is the front axle I was more worried about. I'll check out that other thread in a minute. Thanks guys!!

[Rogan]

The front axle is simple as well. It's a vacuum actuated slip collar that joins two slimed shafts. They're already semi-spinning so you sent joint a stationary shaft to one spinning at 45mph. That's a general description, of course.

[Prowelder]

I gotcha, I've kinda worked on them but not too much. So it sound like I can flip it in and out of 4wd at just about any speed (within reason) as long as I'm off the throttle, correct?

[ISX]

I gotcha, I've kinda worked on them but not too much. So it sound like I can flip it in and out of 4wd at just about any speed (within reason) as long as I'm off the throttle, correct?

[Prowelder]

Correct.

[Rogan]

[Mxrider52]

Yea engaging or disengaging at 55 MPH or lower is what is recommended. I have done up to 45 MPH and have yet to have any problems. I am in the same situation as you. I am driving along and no snow and than all the sudden it turns to ice or snow so I just take my foot off the pedal and give the shifter a good hard pull into 4 HI. Just make sure you pull hard all at once otherwise you will probably get a grind and as far as going back to 2 HI I just let off the pedal and just push the shifter forward without much effort.

[Heavyd1980]

The front axle is simple as well. It's a vacuum actuated slip collar that joins two slimed shafts. They're already semi-spinning so you sent joint a stationary shaft to one spinning at 45mph. That's a general description, of course.

[ISX]

i was told that the 02 trucks dont have the slip collar they are constantly turning??? does anyone know the true answer to this? i thought they were all vacuum actuated???

[Heavyd1980]

sweet thank you ISX, so how much added drag does this involve?

[Rogan]

does it vacuum-actuate the hubs? I do not know.

[Heavyd1980]

they dont have hubs. correct? my understanding is that the axle turns all the time so when you activate the tcase the front axle has power!