Clunk while driving in 4 wheel

[scruffinit08]

Hi everybody. I have a problem with my '94 Ranger. It has auto locking hubs, 4.0 liter. When I'm in 4 hi, there is a regular clunk coming from the front end or trans case I think. When I'm driving at about 55 mph (2500 rpm in 3rd gear) there is a clunk that happens about every 17-20 seconds. My speedo drive gear is bad in the transfer case, so I don't have overdrive or speedometer right now. It only clunks in 4 wheel, not at all in 2 wheel. I haven't seen anyone on here with the same problem, so I'm hoping to get a few ideas to what is going on with it.

 

[kyleb617]

My truck does the same , he has a hardtime going past 40 in 4x4..i dnt believe 4wheel drive is ment for going that fast to be honest, when going that speed just turn it back to auto..just my $0.02

 

[biggmike1012003]

mine does it inɜ 4 auto and 4 low i have talked to a lot of people and they said its normal something about the half shafts

 

[scruffinit08]

I hope it's not normal. I'm going to change that speedo drive gear this weekend to get backo/d and cruise. That should get it running better atleast. The weird thing I wonder about is why it happens at such regular intervals? I put new U joints in the front about a month ago. They were totally shot. I've only had the truck a couple month, so it's an ongoing deal sorting through all it's bugs. Could it have something to do with the chain in the transfer case if that is stretched?

 

[MrShorty]

Yes, if you want to talk about any possibility, it is possible for the chains to stretch on these. It seems to be a fairly rare occurence, though. Certainly not the first thing I'd look at.

1st thing I'd probably look at is your tires. I had a similar situation on my BII during the short interval I was running mismatched tires. The slight difference in size between different tire manufacturers caused a "binding" in the drivetrain when in 4H/4L that would show itself as a periodic "clunk". I also had a difficult time getting it back into 2H.

 

[scruffinit08]

My tires are almost new and the same kind. I'm going to look over the tie rod ends and ball joints and anything else I can tomorrow or saturday. I'll be under there changing my tranny mount anyway. Who knows what the young guy I bought the truck from did to it before?

 

[Blee1099]

There is no reason to be in 4hi and going at speeds around 55mph to be honest.. If it's slippery the 4wd is not going to help one bit at speeds that high. Once you do start to slip, 4wd can't do anything fast enough to help. 4wd may get you out of slippery spots but it won't assist you in stopping.

 

[scruffinit08]

My tranny mount and hanger bearing on the drive shaft are shot. I'm thinkng that after replacing both of those, the binding or clunking might be taken care of. Would it be possible for the harmonic vibration from rpms and road slapping to cause a regular spaced clunk in the front 4 wheel when under load from driving in 4 wheel? That's my new theory. (who knows?)

 

[StangsandMavs]

If it's anything like the 95 Explorer, speedo and worm gear is where I'd be looking. An easy check to see if your VSS is working is to take out the drive gear from the tranny case and hook it up to a low speed drill (I just used a cordless)... then observe the speedometer to see if its giving a good, consistent read while you're spinning the gear...

If it does, then you know that the problem with the speedometer is either the drive gear or the worm gear inside the transmission that drives it.

 

[dave1618]

Honestly guys, from my experience,Owning a brand new purchased 92' ranger Stx 4.0 ,4wd, having it for 6 years, 2 of which with a snowplow on the front, and just last year bought a 91' Explorer 4.0 xlt, Both vehicle equipped w] auto hubs. Stemming Back to 96' I found myself Stripping out the entire front axle, and completely re-building it, 8 mos,later I then noticed the culprit, which was the thing that looks like a jagged end of a broken beer bottle, it's round, plastic,and has an aluminum inner washer, one of them was severed in 2 locations, and barely held together by the springs,the other one was fine, once i replaced it, no more clunking, well at least til i had to rebuild the axle again in 98' {the snow-plow killed the axle sooner} but that piece I speak of is just poor designing, I noticed lots converting to Man-Lockers, and today I checked into it, and the conversion W/ reputable parts Meaning {NEW} would run about $350. for now it doesn't seem cost effective, but perhaps this summer I will make it the project,besides I still like the idea of not getting out to twist hubs. Btw the inner Hub working do need grease but what ever you do, DO NOT OVER GREASE, that was my 1st mistake, Hope all this helped, The old Man !!!