Trans fluid??

[p_justin13]

Need to change any suggestions on best fluid to use?
Thanks

[atilla_the_fun]

Hi Justin,
When I first bought my VX, I changed the transmission fluids out with Mobile 1 synthetic transmission fluid. I didn't have the tools to change the gaskets and the filter so I just changed the oil. A year later I tackled that project again and replaced both gaskets and the main pan filter. Because the fluid was relatively new I drained it and reused some of it, but I filled it back up with an O'reilly brand full synthetic (dextron 5 or 3?, the GM kind). It may have been valvoline, but it was much cheaper than the mobile 1. My shift quality was good when I first changed the fluids, but it did get smoother after I changed the filter.

The moral of the story is that I personally do not feel it really matters, aslong as you use the GM required fluid. If you're like most of us here, and have a VX with >100K miles, then you have similar gunk and deposits inside - so just buying the most expensive fluid (mobile 1) won't really undo any of the wear to the transmission. I would not have dropped the $100 on the mobile 1 fluid.

[PHO2GR4]

Yeah, I'm just going to check my level and top off if necessary. If you don't know what's already in there, what's the "safest" fluid to use, to add to the existing mess?

And where's the best place to buy a suitable plug-and-gasket kit?

[89Vette]

More importantly, where's the fill location? I think I see a plug up high on the DS of the unit, but I'm not sure I could get my hand in to r/r it.

I changed all fluids in my drivetrain except transmission. I'd like to do this too -- if I can figure out how to refill it!

[atilla_the_fun]

I did not see any loss in performance (or any negative issues) when I switched from the ?? fluid in the VX (which was inside when I bought) it to full synthetic. Any GM approved synthetic should be fine to add. Replacing the all the fluid should be safe - just be cautious of transmission "flushes" that are advertised in shops.

You can get the gasket kits from Advance autoparts, and even NAPA. Some stores even carry stock. The VX has two transmission pans, the first is just behind the oil pan, and the other, larger one is behind the first. I had to buy the smaller pan gasket online (from ebay) as it was not available in any of the stores I checked. This smaller gasket is in principle re-usable, but mine was torn when I first changed the fluid.

If you look on the How-to section of this forum, or search google for "transmission fluid change site:vehicross.info" you should find a large database of information and a guide to replacing the filter and gaskets.

[Mile High VX]

More importantly, where's the fill location? I think I see a plug up high on the DS of the unit, but I'm not sure I could get my hand in to r/r it.

I changed all fluids in my drivetrain except transmission. I'd like to do this too -- if I can figure out how to refill it!

Great to directions to more fun than you ever thought possible...

http://www.vehicross.info/modules.ph...warticle&id=20

[atilla_the_fun]

There are two bolts in the main (large) transmission pan. One is on the very bottom, and the other is situated higher up towards the passenger side. The two bolts are separated by maybe 12 inches.

The fill plug is the one that is higher up, and if you slide underneath and find both bolts you will understand. You are to put one end of your filling hose into the fill plug opening, and then using a fluid pump (like $15 at the autoparts store) you fill it with 7 quarts of fluid. Then you close it up, follow the guide on this site to checking the fluid - and either remove or add more.

The drain plug (the bolt that is on the bottom of the pan) has a washer that needs to be replaced each time the fluid is changed. I believe you must order this from Merlin (Call parts at St. Charles Isuzu). I was able to re-use mine by sanding down the washer and using some copper high-heat RTV. No leaks so far.

[PA-99]

Where is the transmission filter? It is not shown in the step by step:
http://www.vehicross.info/modules.ph...warticle&id=20

[Triathlete]

The drain plug washers are available at local auto parts. I like the fiber type. Just don't over-tighten the drain plug.
Filter location...when you drop the main pan it will be staring you in the face. Two bolts hold it in place. Very easy to remove/replace. Make sure to buy your gasket a few days in advance. It will come folded in half...unfold, place on flat surface and place something flat and heavy on top to flatten it. It will make the job a lot easier.
Also be sure to read the refill instructions in the manual. Filling is done hot with engine running and you must cycle through the gears.

[Triathlete]

Also, search my username and trans and you should find a little write up with pictures.

[Mile High VX]

Where is the transmission filter? It is not shown in the step by step:
http://www.vehicross.info/modules.ph...warticle&id=20

You must remove the main pan to change the filter...to do so you must remove the cross member and support the transmission. Your filter should come with the gasket and if you lay the gasket out to flatten for a few days before you use it you'll be glad you did.

[Triathlete]

You can actually get the pan off without removing the cross member if you use a swivel socket but the trans mount has been known to loosen up over time so it is always a good time to check it.

[Mile High VX]

You can actually get the pan off without removing the cross member if you use a swivel socket but the trans mount has been known to loosen up over time so it is always a good time to check it.

Good to know and excellent suggestion on the trans mount!

[VXR]

Need to change any suggestions on best fluid to use?
Thanks

I am using Mobil 1 ATF

[Y33TREKker]

Mobil-1 ATF here also.

With synthetics, it's not just how similar they flow at normal operating temps when compared to regular fluids, it's how well they maintain their viscosities throughout their entire operating range. If you've ever added regular oil to an engine when it's around zero degrees F outside, you've seen how differently it pours when compared to adding it during the summer months. And on the opposite end of the scale, synthetics are designed to also maintain their flow characteristics when hot.

This applies to any full-synthetic fluid though, not just Mobil-1.