although just an 1/8th of tread left the tires appear sound, no dry cracking or loose tread evident. it'll be later this week before I can get to the long incline

 

I would suspect the tires. My truck had a vibration, only at certian times and speeds. Come to find out after new tires it went away.

 

I'm hopeing to get on the hi-way over the steep incline later this week to check coasting in nuetral. is still present then tires/suspension I presume
I don't drive this PU much from march to december 1 usually my trans is my 3-wheel VW m/c

 

to update this thread I drove my ranger over to VA hospital friday and checked the vibration on the downgrade comeing into the county. I shifted into nuetral (auto trans) at 50mph and braked a bit to slow to 35 the vibration was not there. it's present at speed above 35 or so to about 45 or so when slowing down only in drive or OD. although noticeable it's not bad. could this mean a slightly out of balance driveshaft? the u-joints seem to be fine, had the rear jacked up to check them
not present when accelerating at all - got me stumped.
thanks for all replys.

 

OK, good test, so the vibration isn't there when drifting in "N" at the problem speed.
Did this vibration come about suddenly after some event????
Has this drive shaft ever been off & if so was it marked so that it went back in the same orientation????
Have the universal joints ever been replaced????
Is this a two piece drive shaft, if so, has it had the splines relubed with Fords specified PTFE loaded grease????

 

no, the vibration isn't there when coasting in 'n' inside the speed range that it's present when let off the gas. I had to wait for the 'test' until I could drive it on a steep downgrade then shift into 'n'.
I bought it about 2 weeks or so back. it's one-piece driveshaft, no carrier bearing. jacking up the rear to check for slop in rear end revealed no discernable u-joint play. they appear to be factory, I did look over them some (I was checking for zerk fitting) - appeared factory.
I did a look-over of the shaft, there was balance weight on it, other than that I didn't notice.
forgot to say that's over-all vibe, not restricted to steering wheel.

 

I had the chance yesterday evening to drive to other end of county where there's a grade and no traffic and was'nt in a rush to get home.
the vibration seems to be mostly in the steering wheel after all. I have checked thre tie rods and also the hub bearings, all appear ok. the tires up front I have'nt had them balanced, did the rears so combined with about only 1/3rd of tread left I'm rethinking the source, likely front wheel/tire issue since I've done some checking up front already.
I'll keep posted but again it's over 35 to about 50 when I let off the gas and begin slowing down, not there when I hold steady speed - sure got me stumped?

 

OK, well if you've come to suspect that you have a front wheel/tire troubles, to try & isolate which may be the problem, swap them front to back, one side pair at a time & see if the vibration in the steering wheel ceases, or follows a particular front tire/wheel combo.

 

I've got to drive it over to beyond Burnsville NC this weekend, a nephew that's a small engine mechanic is gonna ride w/me to a family function maybe we can figure this out
maybe as simple as out of balance front wheels - would'nt be surprised. I got the backs balanced right off as I was looking for a good used tire to match - lucky the tire dealer had just one so had it mounted to replace the balding tire and spun 'em both.
I've got an idea it's front wheel vibration but as long as steady speed does'nt manifest, just when slowing from 45+ a bit down to 35 or so. from higher speed doesn't do it, the threshold is around 47mph down.

 

I suppose it could be an internal tire problem, splice, belt, ect. Have you had a road force balance done???? They mount the tire on the machine, spin it while applying a calibrated amount of road force to the tread, to cause the tire to deform as it would on the vehicle under load at the trouble speed.

 

no the tire shop I go to does'nt have one of those. if my nephew agrees it's front end (I'm almost sure it is) I'll take it in for front tire balance.

 

OK, let us know how it goes.

 

couple weekends back I made the planned drive - about 200ms packing my aforementioned nephew that's a service tech at a large outdoor and contractor's eqpt rental. there were some down grades where I did the test - into nuetral at the problem speed (between about 35-45 mph) brakeing the ranger slows it down like an anchor has been dropped it will litterally stop on a dime with the new brakes all round the previous owner had done. I could'nt tell the vibration stopped so quickly when the speed dropped if it was present upon brakeing at 45 mph. it is present in nuetral though, my nephew confirmed it but not as prounced as in D. I have'nt though yet to hit the throttle slightly when coasting in nuetral. I drove it today my VA trip and back and reconfirmed the vibration still present when let off the throttle in the problem range, I didn't think to slightly give it some throttle when coasting in nuetral at the problem speed but have when in drive and vibration imediattely ceases so that' s the next test - when I drive to another town next tuesday to dentist. road surface is mostly flat though so ain't sure of results.
thanks to all interested and tips, I can tell you that NC 280 comeing into Pisgah Forest from A-ville Aport is a honey-hole for the Troopers they are worst at Little mountian - an 8% grade w/a warning of reduced speed many drivers miss,
US 64 comeing into Pisgah Forest turning towards Brevard is also a trap area however it quickly gets into developed area and the cops pick up playng HP.

next test - coast in nuetral in the problem range and give a bit of throttle ( this seems to smoothe vib when in gear) to check the last condition of operating. the vib isn't bad, it's just aggravating and if there's a fix that does'nt require remove engine or trans (automatic) I'd do it.
the gathering I attended was a memorial for mom and her sister and mom's oldest daughter (died in Jan) to place their ashes in the Toe river outside Burnsville. another nephew is service manager of one of the if not the largest Toyota dealer in N. Va, he must do plenty good at it as he gets a new 4wd RV every year. I asked him about any sabatog#E he'd run into. one noise that no one could track down he found. a frame welder had stubbed a mig wire in a mostly sealed interior panel then tied the wire to a large nut leaving it to swing like a pendulum. a foto was taken and sent in with the mfr codes and someone got axed
I had thought of chatting w/him about this problem but the man was so glad to get out away from stress (he's 20 yrs younger all gray headed, a spare tire and smokes at least a pack a day, 1.5 or maybe 2. that I discarded the idea so he could get his mind off his job, glad I did he did a great job on the grill next day - took both of us to complete the cleaning, ash removal, get charcoal (kingsford is good stuff) going, took several squirts of starter to get a hot fire to produce ash covered coals - then he took it from there. which was formely my job I'm sure glad he stepped up so well. his youngest son and my 2 youngest nieces did leg work for him and it worked out fine. burgers brats and dogs, and foil wrapped cob corn
I'll post again of the test coasting in nuetral and slight throttle when I get to the longer downgrade.

 

found it. or rather a competent front end mechanic did.
as I suspected a front wheel was out of balance (passenger side) and also slightly warped. given it's a 4wd I'm not surprised. a balance of fronts helped mucho.
located a parts '94 to scavenge a couple hopefully good rims off of.
thanks to all replys Tom

 

Good find fix, feedback & to hear its mostly ok now. Thanks for closing out your thread.