The owners manual of my '03 Liberty equipped with SelecTrac states that shifting from 2WD to Full Time 4WD should be performed at or below 55 mph. What are the ramifications of performing this shift at speeds above 55 mph? The reason that I ask is because I have found myself on the road with posted speeds as high as 70 mph, and have wanted to shift into full time 4WD. To do this, I have been either slowing to 55 when traffic conditions allow it, or pulling off on the shoulder or exit ramp to reduce my speed to allow shifting.

I have had those thoughts myself, and on my 03 CRD I have to go from RWD to PT 4WD to FT 4WD to use the FT option. I would so not want to be in 4WD PT while doing any speed at all on the tacmac. However, I have done it while driving 20kph and the shift seemed to be ok. To engage FT properly I shifted to N and back to D to engage the gear teeth.

What I think is the problem at higher speeds is the gear teeth alignment. If your gears are spinning too fast you are entering a potential dangerous situation for your teeth. If they don't align properly you can expose the teeth for high stress forces which can in extreme situations cause your transfer gear to go *bang* and crack up.

Not saying this with any detailed technical insight, but with a more general overview of the shift procedure.

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Silver 2002 Skoda Fabia TDI, 235,000km
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I suspect that alignment of the gears is correct, because the manual also states that both the front and rear wheels must be turning because there is not synchro; but it seems that if they are all turning at 55 mph or 70 mph, the alignment shouldn't be a problem.

I don't understand why you would need to do this. Just put it into 4WDFT beforehand.

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Have fun out there.

2003 Cactus Green Renegade w/ NP231 & NV3550
Al's 4th Gen UCAs
Custom 3.5" Lift
Rear DTT
Spidertraxed 245/75/16 Maxxis Bighorns

also if I am going 70+ ... and I need to use 4WD .. full or part ... I best slow down to get into a safe stopping distance anyway.

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2005 CRD Limited
added Mopar plates, snow, mud
Detours backbone (w/lp8500)
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