The transmission fluid in the Buick is a light brown color, not red at all, but not dark brown or black either. I plan on having the pan dropped and having the filter changed. I know this will not change all of the fluid but will it be enough to "help" the transmission shift any smoother, or last any longer? As of now it shifts fine when cold, but when it warms up the shifts become firmer and clunkier. Not whiplash hard, just clunkier and firmer. Should a pan drop help shifting right away? Or should I wait and just have the whole thing flushed?
Will old transmission fluid affect shift quality?
- Thread starter gregk24
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Originally Posted By: gregk24
The transmission fluid in the Buick is a light brown color, not red at all, but not dark brown or black either. I plan on having the pan dropped and having the filter changed. I know this will not change all of the fluid but will it be enough to "help" the transmission shift any smoother, or last any longer?
A friend of mine noticed shift improvement going from 12 qts of '9 year old' Dexron III to 4 qts Maxlife and 8 qts of '9 year old' Dexron III, so in her case, yes.
This is for an Aisin transmission
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The Pan drop & filter change will most likely put enough fresh fluid in it to make a difference, Probably still has the original Dexron II/IIE in it & friction modifiers are depleted.
Get part of the old fluid out and put in Maxlife ATF. It's good stuff for the 4T60.
Originally Posted By: clinebarger
The Pan drop & filter change will most likely put enough fresh fluid in it to make a difference, Probably still has the original Dexron II/IIE in it & friction modifiers are depleted.
You bet you'll find a difference. I rescued the 4t60 in my BIL's 92 Ciera with a fluid and filter change. (It was not electronic though some think so-- had a vacuum modulator.)
I also added some stop leak goo, looked like cherry grenadine. Figured a little thicker would help the seals.
I'd go with MaxLife for the 4T60 as well. Having owned and maintained a half dozen GM full size cars powered by the 3800/4T6X powertrain, more with that exact transmission than not, I can tell you that transmission fluid maintenance is one of the most key aspects to both transmission longevity and smooth performance.
With several of my GM Hydramatics, I had great luck with using Seafoam Trans Tune before changing the fluid. I used it to restore some really awful shift quality with my '89 Bonneville, which continued to shift well for the 30,000 miles I drove it (until 152k)
In addition to fluid maintenance, you may want to adjust your shift pressure vacuum modulator (you'll see it sticking out of the transmission, directly down from where the airbox/intake tube is). A quick Google search will give you the low-down on how to adjust.
I personally have had much better success with tranny flushes and total fluid replacement. Theoretically it cleanses the entire system to prevent the detergent in the new fluid from breaking up deposits which can cause trouble. I did the pan drop thing twice an both times the trannys failed shortly after. Flushes I had problems and so far the 4 times I have done them they have performed flawlessly afterwards.
Drop the pan, replace filter, fill with maxlife or dex vi to the correct level. Then drive it until you sell it or it gives up the ghost. Doing a drain and fill every 30k miles after the pan drop is optional
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Originally Posted By: eljefino
You bet you'll find a difference. I rescued the 4t60 in my BIL's 92 Ciera with a fluid and filter change. (It was not electronic though some think so-- had a vacuum modulator.)
I also added some stop leak goo, looked like cherry grenadine. Figured a little thicker would help the seals.
Since the fluid isn't red, I would do a drain and fill first. Then after a week or two of driving, I would then drop the pan and change the filter. Then you'll have more of the old stuff changed. Just my 2 cents.
Regards, JC.
Originally Posted By: JC1
Since the fluid isn't red, I would do a drain and fill first. Then after a week or two of driving, I would then drop the pan and change the filter. Then you'll have more of the old stuff changed. Just my 2 cents.
Regards, JC.
If you don't want to do a flush, then I agree with JC1. Do two drain/fills in sequence. If you don't have an at cooler in that vehicle (I don't know but seriously doubt it), that's easier than an at-home flush. I also agree with SPK20a00, getting all new fluid in is the best solution in the long run.
I really don't like leaving old fluid in an AT that's been there a long time. It's sheared, dispersants all used, etc. Why leave it in?
I also really like MaxLife ATF, great price in gallon jugs at Walmart. Mag1 is also a quality synthetic ATF and comes in two viscosity choices, delivered cheap via Amazon Prime. I have several high mileage vehicles using both and all are doing fantastic - including one with a GM 4L30E - a more finicky unit that yours from what I understand of each - and it works like new.
Originally Posted By: gregk24
Originally Posted By: JC1
Since the fluid isn't red, I would do a drain and fill first. Then after a week or two of driving, I would then drop the pan and change the filter. Then you'll have more of the old stuff changed. Just my 2 cents.
Regards, JC.
Originally Posted By: threeputtpar
Originally Posted By: gregk24
Originally Posted By: JC1
Since the fluid isn't red, I would do a drain and fill first. Then after a week or two of driving, I would then drop the pan and change the filter. Then you'll have more of the old stuff changed. Just my 2 cents.
Regards, JC.
Originally Posted By: gregk24
Originally Posted By: JC1
Since the fluid isn't red, I would do a drain and fill first. Then after a week or two of driving, I would then drop the pan and change the filter. Then you'll have more of the old stuff changed. Just my 2 cents.
Regards, JC.
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