[quote author=rschaer link=board=5;threadid=17433;start=0#163275 date=1058993439]<br>[quote author=Smoke Dog link=board=5;threadid=17433;start=0#163149 date=1058974385]<br>But if you are going to take the covers off, you may want to change to synthetics. Go 75W-140 for towing. Regular driving, go with the 75W-90. I switched to Valvoline Synthetic. No friction modifier required and the LSD works great.<br>[/quote]<br><br><br>What about Friction modifiers for Limited Slip?? Is it necessary or does synthetic gear oil not require it ???<br>[/quote] <br><br>I'd say try it without FM's first, and then if it chatters, get some external modifier and add it to the differential. It seems no two clutch packs are the same, some chatter, some don't. A true synthetic lube will be a PAO/ester basestock, with the esters being the &quot;internal&quot; friction modifiers.

 

Ok, that's a 3500 I suppose.<br>Front: 7.6 pints (you'll need 4 quarts)<br>Rear: 10.25 pints (5 quarts, plus the remainder of the last bottle used in the front.

 

Ok... I'll pick up 10 quarts... since klutzy me usually will spill some anyway.<br><br>Thanks for your help.<br>g

 

I just changed mine recently, and picked up a Suction Gun while I was at the parts store.
Think of a large automotive type turkey baster.
Made filling the diff after buttoning up the cover a breeze.
Very little spillage, and no figuring out how to make the fluid go uphill into the little hole. : ;D
A very worthwhile investment.

 

Hi John, I'm sort of your neighbor, I live down in the Placerville area. I'd be happy to show you how to do this, it's quite simple as has been said already. <br><br>I would make the following suggestions, if you are so inclined and have the $$ to spend at this time.<br><br>Since you have to completely remove the stock diff cover(s) to change the fluid [thanks whoever &gt; ] this is a great opportunity to go to an after market diff cover. The two most common are the Mag HyTec and MagView covers. They range from $200 - $250 each though. There are covers available for both front and rear diffs, I have a MagView on both ends.<br><br>Also, this is a good time to think about going to a synthetic lube, or at least a top quality dino lube such as Lubrication Engineers (I forget the right product for diff lube).<br><br>PM or email me if you'd like to get together to do this.<br><br>Tom

 

<br><br>I'm not against aftermarket diff covers, in fact I have Mag-Hytec trans pan and I can say wth no doubt that it is a top-quality unit that is well worth the price. However, some things to consider when selecting a front diff cover are:<br><br>1. Impact resistance<br>2. Clearance issues<br><br>A few weeks ago, my front diff got hit by a brake drum at an equivalent speed of about 120 MPH (I was doing 60, the brake drum came from a trailer doing about the same speed).<br><br>The stock front cover got dinged up pretty bad, and started to slowly leak because the sealing surface had become slightly distorted. I was able to drive over 500 miles without losing a significant amount of oil. When I got home, I was able to flatten the selaing surface of the cover using a hydraulic press, clean it up and re-install it and it is as good as new, with the exception of cosmetics. The Mag-Hytec is cast aluminum, and obviously I can't say how it would have held up being hit by a brake drum, but steel is tougher and more flexible than cast aluminum.<br><br>The other issue is clearance. I assume that Mag-Hytec provides enough clearance for the track bar rod end on the frame, but If you need to install a Luke's Link you may have clearance problems.<br>

 

You will have a clearance problem if you install Luke's Link.

Man, hitting a brake drum? That sounds like fun.. :

 

At least it was that low - if it had been higher he might have had to change more than the diff cover

 

Yeah, well at least I dodged the tire that came first! <br><br>Actually, I was pretty impressed at how the diff cover held up. Pretty tough stuff!

 

[quote author=emjay link=board=5;threadid=17433;start=15#163315 date=1058997399]<br>Ok, that's a 3500 I suppose.<br>Front: 7.6 pints (you'll need 4 quarts)<br>Rear: 10.25 pints (5 quarts, plus the remainder of the last bottle used in the front.<br>[/quote]<br><br>Interesting, and I have read this before. Mine takes a full six quarts with the stock cover. I do get the half quart or so out of the sludge in the bottom though.

 

That's from the manual ???

 

[quote author=emjay link=board=5;threadid=17433;start=15#163938 date=1059110925]<br>That's from the manual ???<br>[/quote]<br><br>Yeah, thats where I read it before ;D ;D Actually there is an notation somewhere that states that some of them take more, don't remember why, I think it is the pinion angle.

 

OK it's done!! The final number is:

4.5 quarts after removing the cover (rear).

I used the total emjay solution: valvoline durablend 85W140 and the Ultra Grey silicon from Permatex to seal the cover.

Thanks to all who wrote in.

John