CarTalk.com Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

2005 Pontiac Grand Prix

I have a 2005 Pontiac GP with no issues. However, I have had 2 people tell me I need to have my Transmission fluid flushed/serviced. I have 65K on the car…is this something I should do?

What’s the owners manual say?

A standard good practice recommendation is to drop the pan & replace the filter every 30K miles - even regardless of what the manual says.

So - if your trans has never been serviced or if it has been over 30K since service, then you should do this. You will get different ideas about the flush - I would just drop pan/filter. If you do get it flushed the filter must be done before the flush - but not everyone will do that.

The Manual states:

Change both the fluid and filter every 50,000 miles (83,000 km) if the vehicle is mainly driven under one or more of these conditions:
? In heavy city traffic where the outside temperature regularly reaches 90?F (32?C) or higher.
? In hilly or mountainous terrain.
? When doing frequent trailer towing.
? Uses such as found in taxi, police or delivery service.
If the vehicle is not used under any of these conditions, change the fluid and filter at 100,000 miles (166,000 km).

I don’t drive in extreme conditions, so I would assume at 100K I would perform this service. However, what about the comment by cigroller to change filter at 30K?

You will get different opinions on this one. I would consider the owner’s manual as the minimum for this specific item. Personally I would change mine more often. (I have a manual so I do change it, but at about 100,000 miles. If I had an automatic I would change it more often, and I recommend you do so. I would do 50K under normal conditions and 30 or less under severe conditions.

Most people who are aware of regular preventive maintenance procedures (like myself) will change the tranny fluid and filter (if so equipped, some have screens) every 25k-40k miles regardless of use.

My vehicle manuals say to change fluids at set times, (unless there are mitigating circumstances dictating otherwise) even so, I change out the fluids in one half the time/mileage period recommended. Perhaps not necessary, but it’s a peace of mind for me.

No need to flush, just drain/replace and refill.
Only flush if metal is found on the magnet(s) located in the bottom of the pan. (Metal found here may mean a tranny overhaul)

Checking the tranny fluid level and condition (Pink as opposed to a dark red (burnt)) is part of good preventive maintenance and can mean the difference between breaking down when and where you don’t want.

Also consider the cost of a fluid/filter change as opposed to a tranny rebuild or a new or used tranny. ( $80 to $3000)