Transfer case question

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May 13, 2009 | 07:59 PM

shore

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Mountain Pass

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From: Deforest

Transfer case question

Just out of curiosity, is there any way to tighten the drive chain (whatever you want to call it) inside a transfer case? Its an electronic one. on a 2002 superduty.

May 13, 2009 | 08:10 PM

ReAX

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From: Central Florida

I really can't imagine a way to move the input gear and the front take off gear further apart without changing their location against seals. However, it's possible there is a tensioner that presses against the chain to keep it tight.

I'm subscribed in any case.

May 14, 2009 | 12:43 PM

krewat

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From: Long Island USA

There is no tensioner according to my Ford service manual CD for 2001.

If the chain is stretched, you need to replace it in it's entirety.

With the transfer case in 4x4, and the front hubs unlocked (kinda hard to do with an ESOF, maybe jack one of the front wheels off the ground)... rotate the front driveshaft by hand back and forth - how much does it rotate?

May 14, 2009 | 11:37 PM

shore

Thread Starter

Mountain Pass

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From: Deforest

Quote:

Originally Posted by Krewat

I get between 1/2 and 3/4 of an inch of rotation before front shaft catches. I thought maybe that (bolt head?) under the shift motor, might be for taking out the slack in the chain. Ive got alot of drivetrain vibration at highway speeds. Its real bad going downhill, in gear, with no "load" on the throttle. When im going uphill accelerating, vibration isnt there. Ive checked my front axle hub bearings and they seem to be tight.
I'd like to pinpoint the problem before i start tearing things apart just to replace parts. Thanks.

May 14, 2009 | 11:50 PM

rebelchevy02

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From: Milroy, PA

Quote:

Originally Posted by Krewat

You will also need to have the parking break on, to help ensure you do not move the rear shaft at all, which would make it look as if there was more play then what there actually is.

Secondly to the OP, what issues are you experiencing that makes you feel as though your chain in your tcase has an issue? There is usually JUST enough room, so that if the chain stretches enough to actually jump out of the gear, and go to the next tooth, it does not damage the case. It sounds, and feels awefull (yes, I actually have experienced this, with a NP 208 tcase) At that point you take the tcase off, split the case, and replace the chain. If you are thinking this due to excessive noise, that sounds like its near your feet (about were the tcase is) while in 4wd, I would look at ujoints first. So what more info could you possibly provide?

EDIT: Now I see the details. Noise on decel doesnt necesarily mean tcase chain FWIW. If you watch a chain with two sprockets, there is one tension side, and one loose side. While accelerating, one side will be in tension, then on decel, the opposite side will be in tension. Always tension when force is being applied (either direction) I Would seriously examine your double cardan joint at the tcase, and possibly get your front driveshaft balanced. And definetly get it balanced, if you get those joints replaced.