Dana 44: Trac Lok vs Detroit TrueTrac ?

[joedoh]

Originally Posted by 1project2many

Trac Lok is very similar in design to the posi units found in many GM 10 and 12 bolt axles, with a spring applying "hold" pressure to clutches attached to either axle. Both wheels are "locked" unless one wheel presents enough resistance to turning that it can overcome the hold pressure applied by the clutch. As the clutches wear over time they lose their ability to lock or hold the wheels.

TrueTrac is a helical gear type differential that has the ability to vary hold pressure based on the difference in speed between the two wheels. Neither wheel is locked unless one wheel is turning at a significantly different speed. From an engineering perspective, TrueTrac makes fewer compromises. In more extreme situations such as off-roading the TrueTrac generally does a better job than the simple spring loaded clutch pack design of the Trac Lok. Practically speaking the Trac Lok will get the job done in most situations you're likely to be in.

exactly right and to add to that, a clutch type will usually work better on the street because technically it will never "lock", whereas the mechanical locking type will often lock suddenly and wont unlock until the axle speed falls below a limit. I had a no spin locker on a 3/4 ton and when it locked it was sometimes in the middle of a turn where the inside wheel became unloaded and spun and the lockup was sudden enough to make the truck drive straight towards the curb.