driveline vibration

[wfd1064]

ok, any advice on the following.....My 2005 Crew cab FX4 started vibrating after I added 35" tires. I have added 2.5" taller springs on the front, and 3" blocks on the back to accomodate. The dealership repacked the clutching in the rear diff and also shimmed the carrier. The vibration seemed to go away, but now it has come back at speeds over 70mph. I had a custom one piece driveshaft built and removed the carrier. That also helped, but when I hit 75 mph and above, the vibration continued to get worse with more speed. Any ideas?

[Clay Henry]

Originally Posted by wfd1064

Any ideas?

Yeah, slow down...

JK man, Welcome to the ORG

[Raul@Stealth Automotive]

Originally Posted by wfd1064

ok, any advice on the following.....My 2005 Crew cab FX4 started vibrating after I added 35" tires. I have added 2.5" taller springs on the front, and 3" blocks on the back to accomodate. The dealership repacked the clutching in the rear diff and also shimmed the carrier. The vibration seemed to go away, but now it has come back at speeds over 70mph. I had a custom one piece driveshaft built and removed the carrier. That also helped, but when I hit 75 mph and above, the vibration continued to get worse with more speed. Any ideas?

when you put the block in the rear did you make sure you put it on the right direction... so that it angles the axle up a lil bit?

[JBakerFX4]

first thing is to check your angles. without angle readings, we can't tell you squat. the vibes are un-canceled out angles. and pinions like to thrust upward under load and such a bit also. with a 1pc Ujoint/Ujoint you should have 1-2* of pinion upward. thats it. should ride awsome. but remember if your Operating angles in general are over say 10*, it's time for a CV shaft conversion. 2pc shafts are a PITA to adjust b/c you have 3 angles you are working with. and you can adjust the pinion angle by shims, or the carrier by shims. but 2pc shafts don't have as many operating rpm issues and such. thats why ford did 2pc shafts.

[HailTechPDR]

I have a 2006 that I just had a 4 inch BDS lift installed and they shimmed the carrier bearing and we had to keep adding more and testing it. However I still have a vib on take off up to 15 to 20 km and the shop told me that these trucks will have a vibration no matter what when lifted cuz they have a slight one stock. They also told me that basically you can get rid of it on take off, but then you'll get it at higher speeds. If anybody could help me figure out how to get rid of it completely, it would be very much appreciated as I'd like to get rid of the take off vibe before I install the Livewire and want to have some fun.

[makaveli200369]

Are you sure its not the knobby tires causing the vibration?

[HailTechPDR]

It's definately not the tires on my truck, I'm running Mickey Thompson Baja ATZ's, it's a pretty smooth tread as I do all highway and city driving. It's most definately the driveline.

[JBakerFX4]

Use a magnetic angle finder to check the angles on the Tcase output flange and on the pinion flange. Start with that. Post your angles and we'll go from there. After you have your pinion angle shimmed correctly THEN you shim the carrier until the 2pc shaft is "straight". We have a 2pc driveshaft b/c of driveline rpm speeds. you treat the 2pc shaft as a 1pc, but you get advantages of having a 2pc. Less harmonics, terminal speed at which the shaft will blow apart etc. that is why we have 2pc shafts. Vibes on these trucks are coming from incorrect pinion angles.

[dirtbikeguy2003]

I have a 8in lift with 38s and i dont have a single vibration. But my driveline is shimed correctly. Good luck

[Black Pwrstroke]

I have a 2002 also and just put a 6 inch bds lift on it and i shimed the driveline and it has a vibration arounf 50 to 60 mph. Does anyone have a suggestion for me. I havnt got it aligned yet, could that be the prob.