Death rattle

[Ford_6L_E350]

You can tell if it is a coil spring conversion or a leaf spring conversion.

Look at one of the front tires.

If it is a coil spring conversion, it will have a big (6" diameter) coil spring right behind the front tire.

If it is a leaf spring conversion, it will have a ~3" wide strip of metal attached to the frame in front of the axle, going past the axle and to the frame behind the axle.

If you have a leaf spring conversion, proceed with your brake work.

If you have a coil spring conversion, you need to look carefully at all the parts of the steering system. Have someone sit in the van and turn the wheel hard back and forth while you are under the van looking for any free play or looseness in any part of the linkage or steering box. See this thread for more information about a double damper for the steering:

viewtopic.php?f=24&t=4399

Mike

[E350]

Originally Posted by E350

Mine is a Salem Kroger 4x4 as well. Tell me how you lock your hubs. I may have another suggestion.

O.K. even though you didn't tell me how your hubs engage, I will post this for you and others who may come across this thread. [I will also add pictures later when I find them.]

If you engage your hubs by pushing a button while you are in your vehicle, then your hubs are likely engaged by vacuum. The 4x4 converter attached my in-vehicle hub engagement switch to the mechanical vacuum pump which is spun by the serpentine belt. The mechanical vacuum pump powers my brake booster and is entirely unregulated. So higher engine rpms means higher vacuum to the hubs.

Looking at the 2007 F350 Ford Repair Manual for these types of hubs, they are supposed to be actuated by a dedicated electrical vacuum pump which gives a short burst of high vacuum to engage the hubs (i.e., to suck them in) and then lowers the vacuum to just enough to keep them engaged.

The vacuum hubs are disengaged by turning off the switch in the vehicle, then getting out of the vehicle and manually turning the hubs with your hand to "Lock" to bleed off the vacuum and then in 10-20 seconds turning back to "Auto" to put them at the ready for next time you want to engage them with the in-vehicle switch.

Here's the deal, the unregulated high rpm of the mechanical pump eventually caused so much vacuum that it broke off the plastic retaining tabs (which keep the hub housing out-board) and pulled both of my hubs way in-board and into the engaged position - so much so that I was unable to disengage one of the hubs without disassembling it.

Driving with one hub engaged while the other is disengaged is one way to propagate a "shimmy," "rattle," or "death wobble."

To check if your hubs are truly disengaged, make sure that your transfer case is not engaged (i.e., put the lever into 2wd). Then have someone slowly drive a few feet forward and then backwards while you watch from outside the vehicle to see if the front drive shaft is rotating with the wheels. If it is rotating and your transfer case is not engaged, then one or both of your hubs are still engaged.

I ended up replacing my Ford OEM ESOF hubs with new Ford OEM ESOF hubs of the same type. But now I just use them manually. I plan eventually to purchase the 2007 dedicated hub electric vacuum pump, but until then, I have capped off the vacuum line which runs to the hubs.

This may or may not apply to you, because you did not answer my question as to how you engage your hubs, so if it doesn't apply to you, ignore it. And in that case, I hope this post helps someone else.

[JBG]

It has the springs and manually locking hubs. I took it to Les Schwab and they said everything looked tight and the brakes looked fine. i am guessing that i didn't properly disengage the 4x4 by backing up far enough. Its in the shop getting the propane installed on the outside. When i get it back i'll pop it into 4x4 and baja up and down my alley to see if it does it again. Thanks again for all the input.

[E350]

You may want to post a photo of your hubs. Manually locking hubs are disengaged by manually rotating the dial from the "locked" position to the "unlocked" position. Old style non-vacuum automatic locking hubs (like on my 95 Bronco) are disengaged by backing up. Vacuum automatic hubs are disengaged by turning off the vacuum and manually rotating the dial from "automatic" to "locked" for 10-20 seconds then back to "automatic" all the while keeping the vacuum switch off.

I would be very surprised that your "manual" locking hubs require you to back up to disengage.

Again, have someone drive forward a few feet with the transfer case in 2-wheel drive while you watch whether or not the front driveshaft (from the transfer case to the front differential) spins. Then do the same thing in reverse for a few feet. If the driveshaft spins when the transfer case is in 2-wheel drive, then one or both of your hubs are not disengaged.