hi all,I hope is the appropriate section for this.

anyway i was wondering what the best and correct fluids are for my jimmy (2000 model year)
of course the oil cap says 5w-30 but i have a high mileage motor,was wondering if that calls for a change in viscosity also what is the best oil brand for high mileage motors.best power steering fluid,coolant,trans. fluid.
Now about the transmission,I myself usually dont change the transmission fluid at all on my early 2000 GM vehicles(2000 tahoe,2000 jimmy,2002 GMC sierra.)

the reason being that i have experienced it and also have had several friends change their transmission fluid in their early 2000 model year GM vehicles and at first all is well and then at or around 25k miles later transmission goes out.Has anybody else experienced this?Is there a certain type of "special" transmission fluid?Im sure ive left out some vehicle fluids other than the small list in the first paragraph,but i really am hoping someone has an answer to the transmission fluid question as this problem has eluded me for about 8 years.

HAPPY MOTORING!!

 

Flushing a transmission will not break it...if done properly.
Only a failing trans improperly flushed, will break sooner because of flush...but would have broken at some point probably any way.
Edit: there is not really a special fluid...but GM uses Dexron 6 for there flushes now on any vehicle that used to call for Dex3....(I still used dex 3 for my flush though lol, dex 6 was too pricey for me and I know my clutches aren't in the best shape...i'll get a full rebuild when it gets worse though.)

Edit:
When doing fluids don't forget your differentials and transfer case...transfer case takes ATF, or auto trak II if you have the NP8 auto transfer case. (if you have the four button switch on dash you have NP8)

Edit: for engine oil, I stick with what the manufacturer says, and I use mobil 1 full synthetic...others may have other opinions.

 

I agree ^^

The only thing I would add is, don't change oil viscosity. Use what is recommended in the owners manual, or on the oil fill cap. If you use thicker oil, the oil pressure will increase due to the oil not "fitting" between the bearings and the journals. With the increase in oil pressure, volume decreases... which will destroy the engine even quicker. Mobil 1 5W30 full syn, and stay away from Fram filters.

 

How bad or is it bad to put auto tack II in a 3 button transfer case?

 

It won't hurt it, but auto trac fluid is expensive and not necessary because there are no clutch packs. Dexron VI is the recommended fluid for the NVG233 transfer case, (3 button).