clunk coming from drivetrain (rear end?)

[mikracer]

Originally Posted by Gooseberry

I'm talking about the additive that is added to the fluid so you dont get big knocks while turning and don't destroy the plates.

I understood what you meant. We must have been channeling each other since neither of us mentioned the additive by name. Thanks!

[haywoodphotomaccom]

I have a similar clunk, just tried the below and the Ujoints seem tight but the whole shaft does rotate a little both directions. Should it do that and if so how much?

Originally Posted by JackTuppVan

Chock the wheels
set the e-brake
put trans in neutral
crawl underneath your van
grab the drive shaft
slowly turn the drive shaft (back and forth in both directions), paying very careful attention to the u-joint. There should be no slack/slop in the u-joint. If it is really bad, you can hear it clunking when you change rotational direction on the drive shaft.

[JackTuppVan]

"haywoodphotomaccom"

"a little drive shaft rotation" is normal . Here is something i would suggest ....Assuming you have a LSD remove about 5-6 ounces differential oil then add a 4oz. bottle of ford friction modifier top off to the correct level with gear oil .Now take the vehicle to a large vacant parking lot. Drive in a tight right hand circle slowly approx. ten times.
Then drive slowly in a left hand circle approx.ten times.
This procedure, pushes the oil / friction modifier in between the plates and discs in the clutch packs

I use this procedure in LSD equipped Fords that to quiet the LSD chatter in the differential.

[Bellpilot]

I had the same issue, but it turned out to be loose lug nuts after I had a shop rotate my tires.

[BajaSportsmobile]

heyiwantthatphotomaccom... You don't need that!

You have an ARB front and rear and don't need friction modifier.

You are asking about normal drive shaft rotational play. The differential end should have some back lash and axle spline slop that will let you rotate the shaft several degrees. The transfer Case end can have a little more.

[boywonder]

Originally Posted by Bellpilot

I had the same issue, but it turned out to be loose lug nuts after I had a the shop rotate my tires.

Yikes! That's scary.......I hope that was your last visit to that shop.

[haywoodphotomaccom]

LOL Baja, that was my next question/comment as I remember you guys saying that when you installed it....

Now, back to that question......I have a similar clunk on take off....

[JackTuppVan]

"haywoodphotomaccom" I assumed you had a OEM LSD which occasionally have a problem with the clutch packs sticking together which results in chatter or light clunking , friction modifier is used to prevent them from sticking. I didn't know you have a ARB locker. I inadvertently gave you advice that does not pertain to your particular application. Hope you find the source of the clunking noise .

[haywoodphotomaccom]

No worries Jack, I assumed that particular post did not apply to me but was monitoring for other reasons...thx!

One of Ramsey's partners in crime is doing some work on my steering box this week so I'll have him look at this too...

[capnjim]

My 2006 Ford E350 cutaway with a Dana 70 made a clunk when starting from a dead stop. It had 20,000 miles on it. Can't imagine that it was a u joint. For some reason I thought there was a Ford warranty bulletin about clunking rears back in the middle 2000's. Maybe I'm wrong.

All that said my Sterling 10.5 with an ARB is a smooth as silk!

Jim

2006 E350 EB 6.0PSD 6" U Joint

Past Life
2006 E350 21' Quigley C Class 5.4 with 5R100