I got a Weldtec lift kit for my 2003 E350. Jeremy was awesome to work with and I will certainly say that his ability to communicate is top notch and makes the buying process comfortable and awesome.
He went ahead and sent me the updated radius arms and mount brackets. I believe that these are similar to those on a 2014 E350. The way the rear of the radius arm mounts is totally different than my stock setup. The rear mounts with a bolt and nut that passes through left to right ve the rear like my stock setup is.
The question I have is two fold.
1) Torque specs on the radius arm bracket to frame. Three bolts...
2) Torque spec on the radius arm bolt that secures the radius arm to the mount bracket.
My rear radius arm torque is 98 ft lbs. Not sure if this is the same for the upgraded version.
I looked high and low and cannot find the specs. I would call Weldtec but it's Saturday and they are not in.
When I did my front end I just paid attention to what it took to get off and then I put it back together a little tighter.
I also used 648 retaining compound on all the large bolts to ensure they wouldn't come off or vibrate loose.
2010 Ford E350 EB 6" Weldtec Lift
2017 Subaru Legacy
1990 Volvo 240GL
2x 1987 BMW 535is
1995 BMW 540i6