It's been 2 years since I got the beefed up 700r4 and I was wondering when I should service it. Also what do I need to be changing (apart from ATF)? Thanks, Felix

How many miles do you have on it, how hard do you push it, how does the fluid look, do you have an external cooler, what fluid did you use?

This is what GM says but all of these factors play in.

For automatic transmission, change both the fluid and filter every 15,000mi (25,000km) if the vehicle is mainly driven under one or more of these conditions.

> In heavy traffic where the outside temperature regularly reaches 90 F (32 C) or higher

> On hilly or mountainous terrain

> Frequent trailer pulling. Trailering is not recommended for some models.

> Uses such as found in taxi, police vehicle or delivery service (drag racing?)

If the vehicle is not used under any of these conditions change both fluid and filter every 100,000mi (160,000km)

Hope that helps.

Thanks for that. The gerabox has done about 12k miles and I use an external oil cooler. The car is driven hard though. Not sure what fluid was used or what colour it is now...

Is there a service kit for it?

Thanks

There are service kits that countless companies make. They generally consist of a pan gasket and a filter (strainer). I use Redline fluid but if you are going to change if often I think any good name brand fluid is ok (as long as it meets GM standards). There is also another option, when you are changing the filter and dropping the pan you only change about 4-5 quarts out of about an 11 quart capacity (10.4 but with the cooler about 11) some shops (i think even Jiffy lube has them) have a machine (the ones I have seem are made by BG) that pumps almost all of the fluid out and replaces with new fluid, this sound good to me but I am not a tranny guy so others may be able to give advice on this if there is any down side.

If you do it you do not want to over fill if you can use a graduated drip pan so you know how much you took out. The way to check it as per GM is to drive for 15 mi (24km) so you get to normal operating temp. park on level ground and let it idle in park for 3 minutes then check the dip stick level.

First, look at the color of the fluid it should be red. Second, smell the fluid to see if it has a chemical smell. If it is not red but slightly brown to dark brown and it has a burnt smell (slight to strong) then it is time for a complete fluid change. Check the bottom of the pan for black dust (that is not stuck to the magnet) this is band or clutch material, if you see this I would start saving for a rebuild in the near future. If you find the fluid is red and the fluid smells fine, "LEAVE IT ALONE".