I'm currently using LE 1605 and wanted to try Amsoil 75w-110 since its a lil cheaper and easier to get. I was just wondering what type of fluid I can use to flush out the remaining LE 1605 fluid before putting in the Amsoil fluid. Thanks

 

Seems to me the most effective way would be to drain the 1605, fill with 75W-110, drive it around a little (just enough to have it splash all over inside the diff housing) and then drain and refill.

 

There is no need to flush.
Start draining the diff when its hot and let it drain for a while with the car level.
Refill.
Done.
LE leftovers will not "compromise" the Amsoil at all.

 

Here is what Mag-Hytec recommends:
1.Drain oil presently in the differential as completely as possible while the truck is still warm. This also helps remove contaminants and oxidized oil which can impair performance of LE gear lubricants. If contaminated oil remains in the differential, foaming can occur.2.Do not use a volatile, chlorinated solvent or solvent-type flushing compound to wash out the differential. Any solvent trapped in the voids of the reservoir will cause corrosion. Also the presence of even a very little amount of solvent-type flushing compound will reduce the viscosity of a gear oil. Further, without a coating of oil for even a short time, rusting of internal parts of the differential can take place.3.To properly flush the differential, use a light viscosity turbine oil or non-detergent engine oil (SAE 10 or 20). Jack up your truck (no-load condition) and run in gear for 15 minutes and drain. Note that some units can be so badly oxidized that physical removal from the inner surfaces may be required.4.If new gears are installed make sure that the new gears that come with a rust preventative are cleaned off. This insures that any rust preventative, debris, metal chips and core sand is removed before installation. http://www.mag-hytec.com/oil-1605DUOLEC.htm

 

I could see this being necessary under a condition of severe neglect.

 

Okay thanks fellas.