mystery clicking
 

This begins with a story, which ends with me driving through a snowstorm, on the way home from the UP. The snow and wind made it pretty tough, and so traffic slowed to about 45 for the last 70 miles or so until I got home. I put the truck in 4hi, and that made the trip much easier. I know freeway driving in 4hi isn't very good for the front axles, but I never got over 50.

This morning I went to the store, came back, and left again to go clear up my grandparent's driveway. On the way I noticed a slight shutter, and a clicking sound, the frequency of which seemed to be relative to the speed of the truck (probably not coming from the engine). I checked to make sure my gas tank brush guard wasn't hitting the drive shaft, and didn't see that it was, but could have missed it.

My next guess is the cv shafts. A friend said the clicking could mean the impending doom of one of my shafts. What are your guy's thoughts? It could very well just be snow shoved up in a place it shouldn't be, but the associated shutter would tell me otherwise.

as a side note... how difficult a job is a cv shaft replacement? Any warnings on where not to get one (saw checker/advanced/o'reilly has new ones for 105 ea.). If I had the money and time (and a better welder) I'd say this is the perfect excuse to go find a pair of dana44's or 60's... but i don't. If i can find a used one cheaper I might and just say that a SAS is a must before I (probably) hit the UP for school in August.

i know this may sound alittle to simple but did you check to see if anything was in your tires? secondly if the truck is no longer in 4 high the cv shafts should not be turning, if thats the case you could rule that out. also i have drove my truck in 4hi the whole time the snow is on the ground at speeds up to 80mph. and havent had a problem and owned the truck 10yrs!

Another think to check is the wheel bearings, they have a tendancy to click when they start to go.

shouldn't the cv-shafts free spool even when the 4x4 isn't engaged? I mean I'm not sure how they wouldn't because their attached tot he wheels, which are spinning, I always thought the vacuum actuator just engaged the shafts to the diff. so they would be powered as opposed to free spooling.

I hadn't thought of checking the tires... but I am wondering where the shuttering is coming from, as they seem to be related. On the other hand, I could just be nuts and never noticed the shuttering before.

well im not certain i know what i am talking about but that being said, the truck should have automatic hubs that will disengage the cv shafts from the wheel when in 2 wheel drive. i would check tires if there is something big stuck in the tread it will cause a shutter. but i was trying to give you the simplest possiblity. after reading "95 318slt"'s post i would have to agree with him. unfortanitly for you the wheel bearings are made into the hub, and they cost about $110pc. for the front. and upto $50 for rear depend on axle.

Our trucks are not vaccum actuated, the transfer case does everything. When you are in 2 hi, the cv axles, differential, and front driveshaft all free spool together inside the transfer case. When you put it in 4 hi or 4 lo, the transfer case locks the front and rear drivetrains together. If you don't believe me put it in 2hi, jack up the front end and turn the wheels by hand, you can watch all the differnent components spin all the way back to the transfer case (which lets it free spool)

ok never done that, i said wasnt sure if i new what i was talking about.

Hmm... I wasn't sure about the vacuum actuation (I remember seeing the unit on the axle while changing the oil once) so I started poking around the internet. According to Walt the 87-92 (i have a 92) daks have a CAD.

http://www.walt-n-ingrid.com/modifications.html (second article)

I stand corrected! I learn new things about this gen truck every day on this forum! The '95, which is what I have, is completely controlled by the transfer case.

That would then lead to my next question, can I pull the shaft and still function in 2x4? I wasn't sure if the wheel hub is attached via the shaft or not.

does $25 sound like a good priced for a used one? I figure since its used, and I can't be completely sure of it's condition of projected lifespan, that that would be a good deal. found a local parts truck and that was going to be my offer (though I plan to verify my concerns before going about purchasing parts).