Alignment and rear airbags question

[Charles L]

I am having an alignment done tomorrow and a safe t plus steering stabilizer installed. I don't know if the airbags would have any effect upon the alignment. I suspect it will have some effect.

Does anyone know if the rear airbags should be deflated?

[Harvard]

The air bags should be inflated to the height you want to travel because if the rear end is lowered it will effect the front end caster angle.


Make sure you get an alignment report to share.

[toyotech358]

If it's a E-450 it likes Caster 5.5 not 3.5 , 5.5 handles better

[Charles L]

Originally Posted by toyotech358

If it's a E-450 it likes Caster 5.5 not 3.5 , 5.5 handles better

That is what I am asking for 5.5 left and 5.0 right. The other measurements will be set to ford specs. I have a pair of adjustable bushings if they need them for the corrected caster.

[youracman]

Originally Posted by Charles L

That is what I am asking for 5.5 left and 5.0 right. The other measurements will be set to ford specs. I have a pair of adjustable bushings if they need them for the corrected caster.

There is an earlier thread (Shop changed camber to over 6.5? May 15, 2017) that discusses the cross-caster (which provides "lead" to account for road crown.) According to poster Harvard who has been working this (Ford E-series) alignment subject for years, the cross-caster should always be negative; i.e., LH caster minus RH caster is a negative number ..... to allow for road crown. That's the way the Rush Ford truck center in Denver set mine as well...... the LH positive caster is 1/4* LESS than the RH positive caster, so the cross-caster is negative. (BTW- Like you, I furnished adjustable bushings to ensure I got at least 5* positive caster.)

As many others had suggested, I set my rig up like I normally have it at departure............full fuel, 1/2 tank fresh water, air bags at 50 psi, etc and then drove to the Ford alignment shop.

Just sayin'

Good luck ...... and safe travels.

[Charles L]

My mistake.

[OLYLEN]

Right WRONG or indifferent I set my air bags at the level # wise I use. I run mine at 80#, from experimenting with ride/ driveability.

LEN

[n-e-d]

Suggested specs from Forest River for E-450

[Charles L]

left camber .025
right camber .100
left caster 4.7
right caster 5.2
toe +.08

Did not need the adjustable bushings. Toe was way off. I did not get the before readings. Also had a safe t plus steering stabilizer installed. Drives much better now. Still feel the slight drift when an 18 wheeler flies by but much improved and stabil now. I previously installed a rear track bar which I felt gave a 20 % improvement. I would say the alignment and steering stabilizer gave about 40% improvement. It is a motor home so this may be as good as it gets.
The alignment was $120.00 and the stabilizer was $160.00 with my supplied parts.