Chevy Astro and GMC Safari Forum banner

basic (I hope) transmission questions

1K views 12 replies 5 participants last post by  tstol 
#1 ·
Good morning,

I have some (hopefully) simple transmission questions. 2003 GMC Safari AWD. If it helps guide the discussion: quality of cost please.

1) My van has started to pause for a few seconds before going into gear when I put it in reverse or go from reverse to drive. If I wait the few seconds, its smooth. But if I put it in reverse or drive and hit the gas like normal (because that's what I've done my whole life), it'll pound into the gear, for lack of a better way to say it. Otherwise, it shifts smoothly while driving. Thoughts?

2) The van has 120k miles on it. I don't know if the transmission fluid has ever been changed. I have to bring it to a mechanic to have it done. I have learned the hard way that many mechanics don't understand these vans, and the best way to get things done properly is to get the right answer (here) and tell them what I would like done. With that said, I want to have the transmission fluid changed. I know to avoid the word "flushed" at all costs! :) However, is there a recommended transmission fluid? Please confirm that I should also get the filter and gasket changed. Is there anything else that should be done/investigated while they're doing it?

3) I'd like to get a transmission cooler for light towing (motorcycle and trailer = 1000-2000#). Is there one you'd recommend?

Any other transmission advice/preventative maintenance would be greatly appreciated.

Tad
 
See less See more
#2 ·
It sounds like the filter might be a little clogged, the fluid might be a little low and old, and the pressure has dropped.

You want a pan drop and filter change on the transmission. Nothing more.

If you say anything else, they'll want to do a flush or power flush, which is not a good idea at all. They also don't do a pan drop and filter change if they do a flush.

The recommended fluid is Dexron VI. No 'universal' fluid is universal.

All the transmission guys I've ever talked to recommend the B&M SuperCooler trans coolers. They have a bypass in them for when the fluid is too cold - because transmissions need the fluid to be warm, just not hot. My Jeep actually has a setting in the PCM that won't allow the trans to shift into overdrive until the fluid has reached a certain temp.

I really don't think you need to take it to someone. This is something you can do at home. I always install a drain plug when I drop the pan the first time. It's really handy for the next time you drop the pan - the fluid only goes where you want it to go instead of freaking everywhere.
 
#3 ·
Thank you for such a well thought out reply, Leeann_93. Much appreciated. So here comes the stupid question: are you saying the pan doesn't have a drain plug already? That you install one the first time you drop the pan? If so, that's crazy they didn't put in a drain plug, lol.
 
#4 ·
Yes, they do not come with a transmission drain plug, because you have to drop the pan anyway to change the filter. It does make it easier/cleaner to remove the pan if it's already empty, but from a reliability standpoint it's another failure point. That and it would have cost GM $0.12 extra to add a drain plug.

In all honesty I might skip adding the cooler, unless you are in a real mountainous area, a light motorcycle trailer is NOTHING behind our vans. Keep your fluid and filter fresh and your transmission will be happy.
 
#5 ·
AstroWill said:
Yes, they do not come with a transmission drain plug, because you have to drop the pan anyway to change the filter. It does make it easier/cleaner to remove the pan if it's already empty, but from a reliability standpoint it's another failure point. That and it would have cost GM $0.12 extra to add a drain plug.

In all honesty I might skip adding the cooler, unless you are in a real mountainous area, a light motorcycle trailer is NOTHING behind our vans. Keep your fluid and filter fresh and your transmission will be happy.
Thanks for the advise. I want to have the ability to do mountain driving with the bike. I'm getting old for multi-day drives on the bike. I'd rather tow it somewhere and drive around for the week. No matter where I start, I always seem to end up in the mountains, lol.
 
#8 ·
tstol said:
I'm getting old for multi-day drives on the bike.
I'd rather tow it somewhere and drive around for the week.
That's EXACTLY how I do it and feel about it!
(except for that week I spent riding in Oregon and Montana)

011_image012a.jpg
 
#12 ·
tstol said:
Thanks to all who contributed to this thread. Fluid and filter did the trick! With other recommendations about the differential fluids on a different thread, the van is running like new!
Fan-freaking-tastic!

Fresh fluid and filters will keep your transmission happy for a long time.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top