2nd Gen Non-Engine/Transmission Gear Lube Level in Dana 70

[SHermreck]

I have a 01. 5 2500 2wd that now has a pinion seal leak about 7K miles after I changed it. The previous owner changed it at 25K and I did it at around 50K... . both times with the factory 75W140 and friction modifier for the LSD. I filled it to the bottom of the inspection hole but afterwards I have read in some other posts it's supposed to be 3/8", 1/2" below the bottom of the hole. I'm hoping to find out where it's supposed to be and if I caused the leak from overfilling.

 

[jeepullr]

Fill to the bottom of the hole. Over filling would not cause the leak anyway. There is a breather tube that would fill and puke out any over fill. Pinion seals do leak if not put in properly (and even sometimes when properly intalled).

 

[Motorhead]

Before re-installing the differential yoke, use some fine abrasive cloth to remove the polished ring that the previous seal left. Also, try some synthetic gear lube. I installed Royal Purple in my Dana 70. I doesn't need the friction additive

 

[DieselNasty]

Well I noticed I had a minor leak out of my pinion seal so I filled the rear up to the plug. Then the oil just starts running down so I replaced the seal and put in the amount of oil that factory manual said (like 6. 7 pints) of Amsoil 75w-90 and have had no problems.

 

[BigPapa]

Fill to the bottom of the hole. Over filling would not cause the leak anyway.

I think that should be below the hole. I don't remember how far, seems like 1/4". If not somebody will correct me. Overfilling will cause leaks.



Scott

 

[jeepullr]

I think that should be below the hole. I don't remember how far, seems like 1/4". If not somebody will correct me. Overfilling will cause leaks.



Scott

FSM does not list a fill level. Haynes in chapter 1, section 36, item 9: "Use a hand pump, syringe or funnel to fill the differential housing with the specified lubricant until it's level with the bottom of the plug hole. "



Over filling will cause it to foam and cause some fluid to come out the breather tube. No pressure build up can take place if you breather is working properly. No pressure means it can't push past seals. If you are leaking, you've got other problems.