[2007 cummins 6.7 liter]

what is up with that? I thought diff fluid was good for like atleast 50,000. I know the chevys use the same american axle rear differential. How often do they change theirs? BTW I was thinking of using amsoil and changing it every 30,000 unless their actually is a reason for changing it so often.

 

[MATTIAC]

your first change should be done early, but once you switch to amsoil, you can go a long time!!!!!

 

[abonnett]

Once you switch to any high end brand you can go three times as long. I got that directly from a Royal Purple rep and he said that is on the conservative side too.

 

[ban89]

I changed my stock diff fluid out at around 10k miles to put on mag-hytec covers. It was white and full of metal shavings/dust. I put in royal purple and just recently changed it again at 30k when I trussed my axle. The royal purple fluid looked like new. I debated reusing it but decided to swap it out anyway. That was with towing my 12k lb sand toy trailer too.

I'm a huge amsoil fan and run it in all my desert toys. i'm going to try that next time. :thumbsup:

 

[LittleOleHotShotter]

I change out my rear diff with amsoil svo every 125,000 miles. It holds 8 quarts and I always have about 8000-11000 pounds on my rear axle alone

 

[100% Charbroiled]

wow, i didnt realize that we had to change it so soon! i am at 15k so its about that time.

which amsiol severgear are yall using? i rarely tow anything heavy, so would a lighter grade help reduce friction and gain some efficiency? thanks!

 

[Toney198]

wow, i didnt realize that we had to change it so soon! i am at 15k so its about that time.

which amsiol severgear are yall using? i rarely tow anything heavy, so would a lighter grade help reduce friction and gain some efficiency? thanks!

I too am in the same boat. Dont pull to often but I need to change mine. Could I get specs on which brand and weight to get. Also how much di I need for the front and rear. Thanks.

 

[LittleOleHotShotter]

I use 140 weight but i work my truck. For normal driving even with towing, 90 weight will do you good. usually its about 4 quarts for the axle. Just keep on pouring it in till it comes out your hole. First time you change it it will come out metallic black, thats normal. i changed mine at 5000 miles on the ticker. Then I changed it again at 130,000 miles and it was still see thru. lol amsoil should get you 50k to 100k depending on your style of driving. You can check by doing a viscosity test with your fingers and color of oil.

 

[Toney198]

I use 140 weight but i work my truck. For normal driving even with towing, 90 weight will do you good. usually its about 4 quarts for the axle. Just keep on pouring it in till it comes out your hole. First time you change it it will come out metallic black, thats normal. i changed mine at 5000 miles on the ticker. Then I changed it again at 130,000 miles and it was still see thru. lol amsoil should get you 50k to 100k depending on your style of driving. You can check by doing a viscosity test with your fingers and color of oil.

Please help the mechanicly DEclined. Will I need to clean the inside? Or just drain and refill with new? Will I need a new gaskett? Is there a certain torq or just tight? By draining is that acheived by just unscrewing the bolts and letting it drain? Sorry for all the questions but the dealer wants to rape me to let him change!!!

 

[LittleOleHotShotter]

simple job. STOCK cover first time i would take completly off, clean gasket on cover and axle, buy new gasket or gasket maker, brake cleaner the inside all over. gasket it, cover on tighten bolts hand tight or spec it, i just hand tight, pout in hole on side till it overflows. about 3-4 quarts, when it stops overflowing, put cap on it, all done.

Or buy a diff cover, they got drain holes on bottom, just unscrew. Even comes with a dipstick with magnet, and they look cool.

 

[Toney198]

Thank You you have been a big help.:thumbsup:

 

[FiFo]

Stock gasket is reusable, just take the cover off and let it all drain out, first time especially clean out the inside with brake cleaner since there are small metal flakes in their from the brake in of the gears. Put the cover back on and fill it up, make sure the bolts are tight but no need for any kind of exact measurement.

 

[Dale_K]

Prior to 2007 the Dodge owner's manual used to have 2 maintenance schedules, regular and severe duty. The regular schedule did not require a diff fluid change at all for the life of the truck and the severe duty schedule called for changes at 15k. As far as I know the rear axle didn't change with the 2007 model year, the only difference is the owner's manual.

I never haul heavy loads or tow heavy so my plan is to change the fluid at about 50k. If it was good enough for the 2006 trucks it's good enough for my 2007. I think Dodge made the switch to a single maintenance schedule because owner's had a hard time deciding which was the right one to use, so Dodge made it easy and now there's only one.

 

[pricklypete]

I was told the reason for the change is to aviod confusion as to severe use and normal use. We see them in here all the time with diffs that have gotten hot and i mean HOT! (Melted speed sensor anyone?)

 

[BroncoHound]

I changed mine at 20K miles and the OEM gear oil was milky white and NASTY with metal shavings (which is to be expected). I replaced with Amsoil Severe Gear 75w90 (almost 4 quarts for the rear diff, almost 3 quarts for the front diff) and will replace again at 100K miles and probably every 75K miles after that (i like to keep my maintenance schedules organized). Next time I will probably put 75w110 or 75w140 in the rear due to towing heavier than I initially intended with this truck. The front will stay with 75w90, as it should.