Posi-trac lube

[Steve D.]

1) I was told that prior to installing a new posi clutch pack, the plates should be soaked in posi lube. Is this correct, and if so, why?

2) I also read that if a synthetic oil such as Mobil One is used, then the posi lube is not required. Opinions about this?

Steve

[Clem Z.]

Re: Posi-trac lube

because the plates are tight together once assembled will not get any lube between them,so coating them before assy will help prevent this. i have used syn lube since amsoil came on the market better than 20 years ago but i have allways added the GM additive. i have run my silverado 100,000+ mile without changing the lube and GM recommended that the lube should be changed every 7500 miles with std rear gear lube to prevent "chatter" in the turns as the plates try to gauled togethere. after installing a new posi you should go to a large parking lot and make slow figure "8"s to allow the plates to "season in"

[Dave Suesz]

[Steve D.]

Re: Posi-trac lube

I got the new clutch pack from Randy's, and they sent some "blue oval" additive with it. Do you think my 63 will develop a rash if I use it?

[mikemccagh]

Re: Posi-trac lube

Clem: i've had some bad experiences with late model chevy full size pickups and pulling 8k trailers at interstate speeds. All have had posi-differentials. first problem with a 91 K 1500., had about 30 k miles on it with factory rear end lube when , at 75mph hauling to a ncrs convention, pinion seal gave out. pulled over and differential so hot one couldn't touch the case. Still had about 75% lube intact but smelled like it had been burning on the kitchen stove, full blast, for hours.I concluded the heat due to premature deterioration of lube and the heat melted the pinion seal. got a new seal and changed it out on the interstate and made it to anaheim and back. at about 55k miles, the same 1/2ton pickup started making noises in rear. an axle bearing deteriorated. wouldn't have been too bad had chevy used races in the rear axle housing but they didn't on the 1/2 ton rears. had to get another housing out of junk yard.current tow vehicle, a 94 K2500 with optional one ton rear with full floating azle bearings, gave up a pinion seal at 700 miles but no problem since. i have come to the conclusion that changing rear end lube every 25K miles is a good idea. i use Mobile Syn gear oil and Quell addative(spermaceti).regards, mike

[Clem Z.]

Re: Posi-trac lube

i agree if you are going to pull a heavy trailer you need the full floater rear end. i just pulled a open car trailer with a 2500# race car and had no problems with the rear gear in my 2500 series. the most i tow now is a couple of ATVs on a trailer. changing the gear oil when you do heavy towing is the right idea but in a corvette or light duty truck work it may not be a problem.i know from experience that with a posi and regular gear oil the posi starts chattering in the turns after 6/8000 miles.

[Roger Legge]

Re: Posi-trac lube

Mike, I take it the Quell additive is an equivalent to the older GM posi additive that had the sperm whale content? Where do you get it? A Google search didn't turn up anything.

Roger
#36316

[mikemccagh]

Re: Posi-trac lube

Roger: i get it at the local pontiac dealership although it isn'e a GM product. I may have mispelled it--try kwel or kwell. if you can't locate, email me and i'll check it out when i get out to the shop later, mike

[Roger Legge]

Re: Thank You *NM*