Can you change the fluid without taking off the cover? The dealership said they changed the fluid, but they did not take off the cover. The other item is that they showed adding the LS friction modifier and I don't have the LS rear end. Will this hurt anything? I would assume not, but I'm a little pissed they did this. This is what happens when your spouse takes your car in for work...
Before I call them back tomorrow and at least ask for a credit for the friction modifier I want to know if I need to call them out on the entire change. Thanks

 

I guess if they took the fill plug off and then used an extractor they could have. Thats not real common, at least no to me. I did like most here, took off the cover to drain it, cleaned the gears up with brake parts cleaner then used gear oil rtv sealant. Sounds like they took the cheap way out. No way they got all the oil gear oil out that way. Also I like to take the cover off so you know you have a brand new gasket good for another 100K.

 

Probably used a pump in the fill hole which I wouldn't recommend as I agree with Summers22, how would they get all the fluid and clean the gears? When I bought my FX4 used first thing I did was change the fluids and that included taking off the rear cover and replacing the gasket which also allows you to clean the gears and take a look. Not sure why they did it like that as it is not that big a job.

You can buy a replacement cover that has a drain hole, 4wd should come with a cover that has one imho so you can drain the oil out when you hit water.

 

Sounds a little fishy to me. That's why I do things myself, so I know it gets done right. Good luck, let us know what they tell you.

 

Thanks guys, I usually do all this myself, but submerged the rear end getting the boat out and did not have time to do this before I take a 800 mile trip, but I may need to take it back. Any thoughts on the friction modifier in non LS?

 

If you don't have a limited slip differential, no need for the friction modifier. Some differential fluids already have it in (Royal Purple is one); doesn't hurt if you add it to a non limited slip differential, just not needed, and would serve no extra purpose.

 

Can't believe a Dealership did not do this correctly.. I believe their labor rate includes cover removal and replacement. I would definitely get your money back for the friction modifier.

 

When I used to work at a high volume shop, we used to used a vacuum pump to suck all the old fluid from the fill hole. This would get all the fluid out of the diff, but would not get the sludgy junk from the bottom of the pumpkin, nor would this allow us to check the gears for abnormal wear. This would require a full service of the diff for us to pop the cover off = $$$. This service was fine for those that serviced them regularly, as new fluid, mixed with the old would hold the crap in suspension and not let it settle on the gears or pockets of the housing. However, I would always try to do the full service, as it would allow the maximum fluid to be removed, and allowed me to clean the gears. I'm sure the shop that you took it to did one of these quick jobs. Nothing wrong with it, unless you paid to have the cover removed. Also, get your money back for that friction modifier. Won't harm anything, but was not needed.

 

Sucking it out is ok if it's changed all the time.. like NutKase stated but, when it has been submerged in water, you mite want to remove the cover and do it correctly.

 

Called them and he apologized for the friction modifier and credited me back. They did say they suck the fluid out but offered to pull the cover and clean due to salt water potential. Overall happy with the resolution.