i'm impressed that you guys can look at used gear oil and tell the viscosity is not near as thick as amsoil ...

 

Hey now sometimes its not rocket science to tell if one fliud is thicker then another.We had a issue with Nissan manual transmissions.Would come in for a service and what drained out was a lot thinner then the 80w90 the MANUAL called for and thats what we installed.Once the weather got in the 30 degree or less range we had LOTS of complaints about hard shift until warmed up.It was very obvious that the amber fliud that came out of them was much thinner then the 80w90.I ask technical MANY MANY times over the years about this.Got the same old song and dance about the BOOK says etc. Well one day while talking to a engineer about something I brought this issue up.He said he had serviced his own personal Pathfinder and had a cold shift issue after and noticed the same deal on what came out wasn't what went back in. One day I get a phone call from him.He was in JAPAN.He FOUND the tanks that held the trans fliud.It was straight 75wt! He said well GEE WHIZ theres your/our answer.I ordered Kendall 75 wt and it poured like what came out of those manual trannys.No more COLD shift complaints on services or trans/clutch repairs after that.I think a experienced MASTER TECH would have a clue if something drained and felt a lot thinner then what he put back in. I did and I was just a paper pusher.In fact my nickname came from issues such as that.Techs started calling me by it 20 odd years ago.I still use it a lot.

 

like i said ... he could tell that 75W was a lot thinner than the 80W (80W-90 when cold) ...impressive

 

Well I don't think its impressive on how he could tell that or that I could tell the differance in the flow from 80w90 and 75wt. Its real easy.One pours FASTER and feels THIINER then the other.Kinda like 10w30 oil and 15w40.Pour both out and watch and feel.Its not rocket science.

 

You guys kill me.... I just want to know what the factory fill is????? After you do enough tranny services at the 30,000, 60,000, and 90,000 intervals it is easy to tell. I got payed to notice differences be it electrical, powertrain, driveability or whatever. Did you notice my A/C got fixed didn't it. I got the crap that no body else could fix. The typical drag it all over town and it finally ended up at the dealership in my bay. They even saved one for me when I was out sick for 4 days. I walked in the door and the only thing that the service manager said was "I don't care what you do today just fix that van. It ended up being a burnt wire in a connector barried in the dash. I got free lunches all the time. I would get the "If you can tell me what is wrong with this vehicle you eat for free today". I only got stumped one time. Needless to say that car went to the junkyard. Never could get it to run. I still think about that poopoo green Pulsar NX to this day.

 

Good one, HOV.

I'll be on the lookout

 

Can't get a straight answer from AAM or D.C. about fliud or additive one says DON"T USE because it will affect or compromise how the lock up of the anitslip works and the other says use.Plus if the factory fill is not as heavy a weight as 80w90 then why in the world is a thick as honey 80w140 needed. Besides GEAR oil and I can also tell the differance between the thickness of 2% milk and whole! Thought every one could.

 

I think the factory fill on these is made by Texaco. (called synstar?) My understanding is you don't use an additve in your oil. I seem to remember a thread on TDR a few years ago about not using Amsoil for some reason.

I have had good luck with Mobil 1 myself in my previous truck. Towed to California and back with no problems using 75/90. When I was going to change it I went to the dealer, and the parts guy told me all they use is Mobil 1.

One other bit of useless information is that GM has their own "special blend" of oil (very $$) that they insist you use in their rear diffs. They use a similar AAM, but I can't say for sure if it is the same limited slip.

 

According to CARSON DODGE and a few others theres a memo that you might have or should use a liminted slip additive per D.C.and the 06 sevice manual.Also a queston about the 90wt verses 140wt issue and nothing in print that anyone can show or prove.I know I got this BAD shudder after towing 9k 800 miles and found other old posts stating same issue with various brands of gear oil and the shudder on take off was fixed by liminted slip modifer which AAM says DON"T USE but supposly D.C.says USE.

 

dont tell dodge, i think thye reccomend changing it at liek 13,000-15,000 or somthing really off the wall like that.....trying to cover their a** when it coems to warranty work

 

I can also tell you which oil is 15-40 and which is 5-40 when they are both at operating temperaure, just by looking when it drains. Everyone says 40 weight is 40 weight no matter what the low temp weight is, not in my eyes.

 

somewhat off topic - but how much oil do the axles hold each?

 

I looked in the service manual about the lube spec for the rear diffs. It said in the lubrication section that "trac lock" differentials require a limited slip additive, but the "trac-rite" does NOT. The AAM 11 1/4 differential has a trac-rite. I think some may be confused with the terminology with trac lock and trac-rite, but clearly both the manufacturer and DC say not to use limited slip additive.

Why don't you just try the 80/140 and/or the limited slip additive see if it cures your problem? Can't see it hurting anything.

 

Per the manual it is 15,000 for severe duty and 30,000 for normal duty. With the pulling that my truck has had it is normal duty. It's had some but not much. Just got a new trailer so that's going to change. Still won't do it at 15,000 because that is a waste of money. Probably will still service it every 30,000.

 

It's 4 to 4 1/2 quarts for the rear and if you have 4wd it is 3 to 3 1/2 quarts for the front. It's in the owners manual.