preferred air pressure for 395s?

[winfred]

just took my first trip around the block this evening and it rides nice but is a mother to steer, it seriously doesn't really wanna turn (thought i was going to smoke a street sign turning onto my street) but as road surfaces change it turns better on some, it returns to center ok. definitely not a transfer case issue of being engaged as i changed that too (sprag to air shift) and haven't installed the front driveshaft yet, flipped the 331-s2 3.9* spring plates for radial tire caster correction, have 50# in fronts and 45# in rears at moment, i tried searching but didn't really hit on anything

 

[Csm Davis]

Go up until the scuffing on the tread isn't on the outside edges then back down a few pounds until it returns that should be the correct pressure for what you are running

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[winfred]

was moving it up on the driveway and it was hard to steer then a pop and a couple small ones and it was easier, wonder if i have a spider gear issue? still haven't installed the driveshaft but the air is now plumbed to the new transfer case and it locks the front flange when switched so that's the last step, when i drained the nasty fluid out of the diffs it didn't have any metal on the magnet. i may get some avm hubs to isolate the issue till i feel like pulling the axles and chunk out to investigate, kinda wanted the hubs anyway or i'd despline some caps

 

[winfred]

installed driveshaft and went for some seat time in the field down the street and it's fine off-road where the tires can slip, i think this was existing now that i think about it as i remember the pop pop pop occasionally on steering but the NDTs were more willing to scrub. lockout hubs are on the way, if i didn't know better i'd think someone dropped a detroit locker in the front diff, any way of verifying besides pulling the 3rd member? it doesn't make any noises with the front axle engauged and when i ran it up the bank behind my house it happily spins all 6 with no noise or skewing

idles up to about 45 degrees before slipping, i think if i hit it it would go over and right in the canal, definetly better traction then the NDTs

 

[winfred]

avm hubs installed and its fixed, i am all but sure its got a locker in the front now, when i pulled the last bolt out of the first cap it sprung forward to about the next bolt hole. hurt my shoulder on the last test drive horsing it around a corner but took it around the block anyway, i almost wanna put the NDTs back on and play with it, probably drives like a sports car compared to the way it was, steering wheel doesn't unwind like its motorized now, i chalked that up to the weight of the haus on the back and the tandems pulling it straight when it had the NDTs

 

[someoldmoose]

For ANY vehicle ; find the correct air pressure by drawing a line across the tread from edge to edge with a tire crayon or chalk. Drive straight ahead a few tire rotations ( do not steer left or right ). Look at the line you made. If gone, pressure is right on. Outside remains ? Lower pressure and repeat check. Center remains ? Increase pressure and repeat check. This works regardless of tire size, width, or load. Obviously, overloading is dangerous at any tire pressure.

It appears you figured out your issue wasn't tire related but my advice applies to everything from a Smart car to a HMETT. Drive safely.

 

[someoldmoose]

If you still wanna know if the front has a locker, jack up one side, let the other remain on the ground. If you can not turn the side that is raised . . . Locker. Or something broken inside pumpkin. Lockers will also "bang" or "rattle" while cornering. ANY power input while the wheels are turning equals instant loss of steering.

 

[winfred]

i was thinking of trying a lazyier way of unlocking one hub and climbing the bank behind my house again and see if it'll still pull a front wheel, it burned all 6 when i got to about 45 degrees

If you still wanna know if the front has a locker, jack up one side, let the other remain on the ground. If you can not turn the side that is raised . . . Locker. Or something broken inside pumpkin. Lockers will also "bang" or "rattle" while cornering. ANY power input while the wheels are turning equals instant loss of steering.

 

[someoldmoose]

Your way sounds a lot more fun. Won't tell ya fer sure though. All 6 might just be at the same coefficient of friction

 

[Csm Davis]

If he unlocks the passenger side and still spins the driver he definitely has a locker or welded differential, because a open differential will not spin a locked side if the other is unlocked.

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[winfred]

took a good test drive today and when i got back to the house i locked up the left hub then hit the hill again and it burned the left front tire confirming a locker in the front diff

 

[silverstate55]

My Deuce is pretty heavy (lots of tools plus crane in bed, 7 total 395 XZLs with run-flats & steel MRAP rims, adapters; second fuel tank, lots of extra weight) so I run mine at 85-90psi. No irregular wear on tread crowns, and it keeps EGTs down....any less pressure really skyrockets the EGTs when trying to get the beast rolling.

If you're empty (like most Deuces are) then you should be OK in the 35-45psi range, do the wear check like someoldmoose detailed above.

 

[saddamsnightmare]

April 30th, 2017.


I used to run higher pressure in the fronts, say 60# for a deuce, and on the road it made the truck much easier to steer before the air assist was added.