I have an '04 QC Dak w/ the 3.7L but there are very few guys in the 2nd gen forum with this motor, so I decided to post here.

I was to change the trans fluid and the rear end fluid to synthetic (amsoil or something similar) because my truck is 7 yrs old, has 45k miles, and I doubt any of this has ever been done. I have never done it myself, and want to make sure I dont screw up. I'm assuming it's pretty straightforward and I have done harder in tehe past but can someone give me a simple tutorial on how to change the fluids and what fluids are best? I do some light towing (about 2500-3000 lbs) fairly often so I want to make sure my truck has the best.

How do I drain the trans, do I just remove the pan, scrape off old gasket, replace gasket and refill?

How to I change the rear-end fluid?

Thanks a ton.

 

If you want to change all of the trans fluid, you'll want to go to a shop that has a machine that pumps new fluid in while pushing the old fluid out. That's the only way to drain/refill all of it.
The rear end is much easier, just remove the cover bolts, bottom first and let it drain, then clean the gasket surface, replace gasket and cover.