Changing out fluids

[2000 GMC]

My truck has 58K on it. Dropped it off at the dealer to have it checked out since it will be out of warranty soon. He gave me a price list on services. He want's $159.95 to change out the front defferential with synthetic and $79.95 to service the transfer case. How difficult is it to do this? I can use the lift here at the auto hobby shop so it will be easy to get to. What kind of fluid should I use?

 

I had the rear differential and transmission done last year so these are the only things I need.

 

Thanks in advance.

[ness5575]

those are some outrageous prices. you could do it yourself for $30-$40 in fluids and an hour of your time. check the guides section here to get some further info on how to do it, but it is basically a drain and fill for both of those.

if you have the pushbutton "autotrac" trannsmission, be sure to use the "autotrac II" blue fluid from the dealer.

[seadoons]

I agree with the above post. Those prices for the front differential is outrageous - it is as simple as dropping the front skid plate (4 bolts) to get to it, draining it and refilling it. Be sure to take the "fill" plug out first in case it won't come off - that way you won't drain it and then not be able to fill it up. I didn't do my transfer case, I had it done. Now that I have acutally looked at it I have found that it would be very simple too. It has a drain plug and a fill plug. Consult your users manual or serch the net for the exact amount of fluid each takes, but also be sure to buy the transfer case fluid from the dealer (autotrak II)

[RyanbabZ71]

He want's $159.95 to change out the front defferential with synthetic and $79.95 to service the transfer case

 

man I am in the wrong business.

 

this is what you need

 

2 qts diff fluid (synthetic 75W-90 is like $6.99 a qt)

2 qts autotrac fluid (its like $2.99 a qt)

1 pump (to put on the quarts to make it easier adding the fluid est $4)

2 t case plugs (replace the originals and they arent expensive at all)

 

Id say your looking at $25-$30 if you can get some of the items on sale. Probably maximum 2 hrs of work. Even if you have never done these before its not hard. I have never done them before and I found it to be fairly simple.

 

Check this out in the middle under other there is a guide to change the front diff fluid

 

Also I have the t case fluid change outlined in a PDF file. Email me and I can send it to you

 

http://www.gm-trucks.com/IAR_index.shtml

[gnutruk]

All the posts above have it right.

 

At those prices you are being major ripped off. That dealer must have some serious payments due on his Jaguar and his condo in Maui.

 

I have changed all my fluids, and you don't even need a lift (though that will make it easier).

 

The front diff. and the transfer case are actually easier to do than the rear diff., because you do not remove any cover. Just drain, then refill. On the rear diff., it's a good idea to remove the rear cover to clean the gunk off the magnet that's on the inside. Then, when you finish the rear diff. job, it is also a good idea to replace the gasket.

 

On front diff. and transfer case you do none of that.

 

I just cannot believe how outrageous the dealers have gotten. On the other hand, those sorts of blatant prices are forcing many more people to come to forums like this for advice and encouragement.

 

So in response to that, the dealers will raise prices even more, thus bringing even MORE folks here. On balance, then, we benefit !!!

 

gnutruk

[bigdogs]

On the 11.5" rear you don't have to remove the cover either as the magnetic drain plug is at the bottom.

 

RyanbabZ71, I am curious as why you suggest to replace the TCase plugs.

[seadoons]

RyanbabZ71, I am curious as why you suggest to replace the TCase plugs.

I am curious too!

[asilverblazer]

Wasn't replacing them suggested in the guide?

[bigdogs]

I don't remember seeing it mentioned anywhere about replacing them, that is why I was wondering why he suggested to do that, maybe I overlooked something...

[RyanbabZ71]

The drain plugs are aluminum and the case is magnesium. I read somewhere that you should change the plugs after you remove them because of the aluminum material. They are very cheap and make sure to torque them to 15 lb-ft

[bigdogs]

The only reason I can imagine is corrosion between dissimilar metals, but that can be prevented with anti-seize or teflon tape. I would assume then you'd need to change the plugs (or atleast plug) everytime you just open the fill to check the level then too?? There are a few GM Techs on the diesel page I visit, I'll have to ask them about that..

[99silveradoz71]

I'm not the most mechanically inclined person to say the least, but even I will suggest doing them yourself. You'll know they're done right and you'll have a sense of accomplishment.

[bigdogs]

Ok I asked a GM/ASE certified master mechanic and he said the plugs are meant to be reused. I would think having to replace them if you remove them kinda excessive since by checking fluid you'd need to replace them..

[JimG]

I was thinking of doing the same thing to my truck this weekend. After all that rain in the Northeast, I had to travel through a few flooded roads. Definitely want to change the T-case, and since I'm there the front diff's going to get a change as well. The only reason I have confidence in doing this is because of the guides and advice I have read here.

 

Got one question though: What do you do with the old fluids? Front diff is oil, no biggie, that'll just go with the regular motor oil to recycling. What about the T-case fluid? How do you get rid of that? (and no, I'm not pouring it down the drain, tossing it in the trash, or any other "creative" solutions).

[chris_kucia]

I believe the transfer case fluid can be treated the same as you would transmission fluid.