Should 4x4 be louder?

[harriw]

Hey guys,

Got my truck in the end of January last year, so this is my first significant winter experience with it and I don't have anything to compare to. It's a '94 4x4 (electric T-case) w/ 4.0, 5 spd, and ext. cab. Originally had auto hubs, but previous owner put on Warn manual hubs.

When in 4x4, should these older trucks rumble/vibrate a bit? I can feel it in my feet, and I can see the steering wheel vibrate slightly. As for sound, it just sounds like the exhaust gets much deeper and louder.

My only other 4x4 vehicles have been much newer ('03 trailblazer ext. and '04 Sienna AWD) so I'm not sure what's "normal" for older 4x4 systems. It seems more noticeable when actually in 4x4, but seems to do it a bit with just the hubs locked too. I also have 200 lbs of sand in the back, plus it's been pretty much filled with snow lately.

If this isn't normal, any thoughts on what might be wrong? I'm not opposed to tearing apart the front end this summer, but wouldn't know what parts to keep and which ones to replace...

Thanks a lot guys!

 

[Beanmachine7000]

I'd check and make sure everything is tight like it should be, u-joints and whatnot, you should be able to narrow it down within a few minutes...

 

[harriw]

OK. What sort of slop should I be looking for? Should there be any play at all in the axle shafts, etc. in the in/out direction? Obviously up/down and side-to-side is bad, but should there be a tiny bit, or none at all?

I'll check the axle shafts as best I can and the front drive shaft. Anything else I should check?

I'm fairly sure I'll be doing balljoints and tie-rod ends come spring, so that would be a perfect time to do any other front-end stuff. The truck has 172k miles on it, so should I be replacing any other front-end parts while I have the knuckles off anyway? U-joints in the axle shafts would spring to mind, but is there anything in the front differential (or else-where) that I should replace/clean/etc. while I have it torn down that far too? Don't want to have to tear it down that far again soon after...

Thanks!

 

[zukirider21]

definatley u joints, wheel bearings, wheel joints, and any seals for sure while you're at it.

 

[Beanmachine7000]

Everything should be relatively tight... IIt's definitely something that rotates making a problem...

 

[harriw]

Yup, I was definitely planning on new inner and outer wheel seals and possibly new wheel bearings (and spindle bearings) depending on their condition (may just re-pack them if they look good) while I'm doing the ball joints.

I'll get under there and poke around as soon as it gets back above freezing and stops snowing (could be a while......) Is there anything IN The differential I should be looking at? Seals or bearings in there that I should worry about? Or do they take care of themselves as long as there's plenty of fluid in there?

When checking U-joints, you're just looking for any slop between the yoke holes and the bearings cups that sit in them, right? Or maybe slop between the bearing cup and the body of the joint? I don't know if I have greaseable joints or not, but I suppose they could probably use some grease if they're not sealed...

Thanks again!

 

[rkneeshaw]

When you lock your manual hubs the entire front driveline still spins even if 4x4 is not engaged at the transfer case. If your hubs are always locked in and the rumble is only experienced when the transfer case is engaged (from the button on your dash), then the problem is in the transfer case. If you still get the rumble without 4x4 engaged from the dash but with the hubs locked, then the problem is likely u-joints or something else in your front driveline.

I speak from experience. Just had a bad ujoint changed in the front drive shaft that fixed the rumble and devastating gas mileage while front hubs were locked but without 4x4 engaged from the dash button. Now with my hubs locked in and 4x4 disengaged at the dash my gas mileage barely fluctuates from pure 2wd mode and the truck sounds quiet and smooth. But I obviously have the same issue as you inside my t-case because when I actually engage the 4x4 from the dash I get mad rumblings and the truck doesn't roll freely (almost like my brakes are partially engaged). It still works, but it just doesnt sound happy. So when I get a couple bucks she is going back to the shop to crack open the t-case and have a look around

 

[railman]

ok....yes the front end will have noise, vibration, and harshness when the hubs are locked in no matter what the transfercase is doin ( 2wd or 4wd )

that is just common to TTB's....

like was posted before, when you lock your hubs you are now spinning the front axles, 5 u-joints, and the ring & pinion that are normally "static"....that is just normal.....

now if the wheel feels like it is gonna vibrate out of your hands...then that is when ya need to check the u-joints in the front end....

l8r, John