I have the 2008/ 2500 with deletes and smartry Jr
two weeks ago had rear U-joint replaced and all seemed fine started south with 16,000 lb. 5er in tow and on occaision noticed vibration at about 55 MPH on uphill grade , and would stop if went to lower gear. Any ideas as to cause ???

 

well first of all 16000 on a 2500 is way to much weight in my opinion.
they might not have gotten the u joint in stright and scared some of the roller bearings inside the caps.

 

Why wouldnt you tow 16k with a 2500? 2500 is just a number if your truck isnt stock, i pull up to 20k with no problems @ all

 

My guess is the u joint wasnt put in straight or the bearings in the cap are off or missing some. I agree with whiteeye42

 

well for one reason the GVRW would most likely be overloaded
second reason the RAWR would be overloaded on the pin weight
third reason the gross combination weight would mostly be over what the truck should pull.

I pull with a 3500 dually and if i would load my 5th wheel up to max gross which is only 14500 i would be overloaded on the combination weight and my GVRW would be over what the truck should pull according to the door stickers.
I know it would pull a lot more than what the stickers say but if by chance you ever got in a wreck pulling more than you should your insurance might not pay and the dot can nail your butt for being overloaded.
but each to their own do what you want it is your truck

 

Sorry if I offended you, was not my intention! Point well taken with your post.

 

Sorry to misslead, actual weight is 13,923, I also thought the engine did the work, I pulled for over a year with a 2007 5.9 diesel and had no problems , I thought the 6.7 would be better.
It has no vibration in 5th gear or when not pulling the 5er,
I checked Tranny fluid level and was not quite full would that cause problem when in 6th gear ( 6 speed auto ) ?
Is it perhaps luugging when going uphill in 6th gear at 59 MPH then downshifts to fifth and problem goes away ?????
The 2007 5.9 did not have the 6 speed auto Tranny. and I had no problem.

What do you think Guy's ????

 

not offended mpowell was just answering you as to why i thought the 2500 should not be pulling 16000lbs

 

diklohill with the 5.9 what was your rearend gears and what gearing do you have in the new truck yes it could be just lugging the truck in sixth gear but i pull my big 5th wheel in overdrive and i don't have any vibration and my truck is a 2008 6 speed auto with the 6.7

 

It is not a good idea to tow that 16,000lbs in '05. I think that it is really the main cause. And I suggest that you should lessen the weight of it.

 

Sorry to sat taht I am a novice as a truck owner this is just now going on my second year of ownership , and I do not know for sure the gear ratio but I am fairly confident that both trucks had the standard equipment and no special orders as to drive change spec's , just the standard equipment

 

My dually did that a couple times, auto w/3:73 gears, I now use the auto-stick button alot. someone said the 6 sp auto, had like 2 overdrives.

 

Soooo, Sabercat ??? Your simple solution was to manually shift into 5th gear or Manually shift into 6th ???? what did you do , for after surfing web I do think it is caused from lugging at low RPM's ( too much drag on tranny in overdrive ) By the way I also went to Reputable Mech and ask about problem, and strangely one of the first questions he asked ( was this while you were in overdrive ? ) he is going to check it out Tuesday .
AND by the, way what in the heck is Home Depot Modified air box????

 

I don't rely on the computer to say when to downshift, it will lug it down too much, at least with my 3:73's. I usually only have to manuely shift, on say 55mph roads, when I'm on the freeway, I drive about 63-65 loaded, and I don't have to manual downshift. On 55 mph roads, I keep the shift indicator in 6th gear, not (D) that way, just one click to 5th gear.
The HD air box is, get a dryer vent thing-a-majig, like what you would hook the dryer hose to. Cut a 4" hole in the bottom of your stock airbox, and put the dryer vent scoop in, it has a flapper also, that I pop riveted open.

Heres a link to one, cut some of the pipe off.
http://www.homedepot.com/h_d1/N-5yc1...atalogId=10053

 

i'm a little confused , what is the stearing wheel selector set on if not set on drive ? My manual shift is a simple little push button on the gear shift lever .
So , It sounds like you just opened the air box more and added a home made air scoope