Help, Following up my last posting on my '02 PSD vibration. First, Ford tech says "I can't feel it". Now, tires are not the problem, I had them balanced (they were out a small amount), I played with the air pressures and still get that resonant vibration. What is a sure, predictable thing is this.......At 1250 rpm, the vibration is there!!!!!! but most noticebly between 40-50 mph, closer to 40. I have the E4OD. When I play with the gears and hold the same speed, the vibration goes away. Then when I get bact into the 1250 rpm range, it comes back. Also, I go to neutral at 50 mph and coast to an idle, and the vibration comes up and goes away, I assume this may be a tire issue.....not that bothersome..... Is there anybody that has had this problem???? Is it just a normal resonancy of the PSD, or am I just too sensitive to vibrations????????? Anybody???? Thanks! appreciate all the good stuff from fellow owners.

ceejay

 

Have the slip yokes and u-joints been checked on the driveshafts? Did you lift the truck? If so, you may have to shim the carrier bearing.

Les

 

Les, the truck is stock.....no lift. As a matter of fact, it is only two weeks old with less than 1000 miles. I also thought about driveline. Everything is tight, unless maybe a u-joint or hanger bearing is binding..I just don't know.


ceejay

 

Very confusing from a diagnostics standpoint, the mechanic can't feel it? It must be very low amplitude. What is confusing to me is that you describe the condition as predictable at 1250 RPM yet play with the gears to hold the same speed at the same RPM, not possible. You might go through the gears and hold the same RPM and have a different speed at a common RPM. Maybe it was just the verbiage. The coast down sounds like resonance. Without something to quantify the amplitude in velocity, acceleration, displacement or phase you have to go with a much less accurate criteria, opinion by feel. Assuming you don't have access to a vibration analysis data collector try this, get a friend to drive the truck, one that doesn't know anything about the problem. Run it down the freeway up to 70 then casually mention to him that you thought you heard something, let it coast down through 40 MPH on a smooth exit. Don't give him any clues. If he feels it then find someone that has a PSD and let him drive it. Do the same thing. If they both feel the vibration, and think it's significant, then run the cause down. If not, you just might be vibration sensitve. Worrying about all the underlying rare but possible mechanical problems you might have will take all the FUN out of having a PSD. If that is the case it is an easy problem to repair, just ignore it and enjoy your new truck. You have the best thing on four wheels, the best engine, the best tranny, frame, man years of engneering went into it so you could use it and enjoy it.

 

Oneof6, What I meant was to hold the same road speed and let the rpm's fluctuate to change the amplitude of the vibration in order to pinpoint either driveline or something else. I do know several other owners of PSD's and am going to try your suggestion. Maybe I am just sensitive to vibrations.....those that will come with a diesel. This is the first one I have owned, but have been using them for years for work......from the first 6.9 all the way up to the PSD. I appreciate your reply and suggestion.

ceejay