To flush or not to flush

Post by **cweberj30t** » Tue Nov 11, 2003 10:05 am

I spoke to someone at Scottsdale today, I beleive his name was Greg, to order a transmission filter and gasket. He said that doing a flush might do more damage than good. I have a 93 J30t with 80k. He suggested just doing a pan drop, filter change and refill. I wanted to switch do synthetic since I've heard good feedback from using it. What are your opinions?

P.S. He also told me that the bolts are only torqued at 7-10 ft lbs. Is that all?

Post by **Jeff Williams** » Tue Nov 11, 2003 10:05 am

My Q transmission was shifting fine, and had 60K, since the rebuild. I did the flush, and it is shifiting a little hard, from 1 to 2.

As far as the torque, I would say 10 was the absolute MAX. more like 7 to 8. I have stripped a few bolts in an old TH350 aluminum housing, before I realized my mistake. Most transmission torque settings are in Inch-Punds, not Foot-Pounds. I was trying to get to 12 ft-lbs, and could not get there. I was set at 12 ft-lbs.

Not real proud of my mistake, but thought you should know.

Post by **cweberj30t** » Tue Nov 11, 2003 10:05 am

Thanks for the info. Much appreciated. So would you be for or against?

Post by **Jeff Williams** » Tue Nov 11, 2003 10:05 am

Let me start by saying I am a shade-tree mechanic, who used to build race cars, in the 80's and 90's. Mostly GM and Pontiac, for NASCAR. I started at the bottom, and quit as a crew chief on a "Daytona Dash" car. We spent most of our time with 4 speeds, but I have worked on several automatic transmissions, and even built a custom one, without a torque converter (never really worked right). I am no expert on synthetic oils, and don't claim to be.

Now, having said that, I say: "if it ain't broke, don't fix it."

I would drop the pan, replace the filter, and send a sample of the transmission fluid to a lab for analysis. I do not know of one, but a search here, or on the internet might pop one up.

If you want to go synthetic, I don't think an 80K transmission is the one to do it with.

I am not unhappy wiht my flush. I did not go synthetic. I just have to now add some Lucas treatment, until the shifting is right where I want it.

A flush will clean the transmission out, and synthetic oil will handle the heat better, but I don't think an 80K transmission will last any longer, because of either.

If you are looking for better shifting, try a treatment first, then move th the pan drop, and then to the flush, and finally to the synthetic oils.

Just my opinion.

Post by **elwesso** » Tue Nov 11, 2003 10:05 am

If the fluid is in bad shape, a flush will certainly kill it....

Over on cadillacforums, the 48TE (or whatever it is, cant remember off hand), if the fluid isnt changed at all, it usually starts slipping at 120k (pretty impressive, IMO).... EVERY time the transmission wont shift after a fluid exchange, much less a flush.....

If the fluid is really bad and you dont know when its been changed last, I wouldnt change it or you'll kill it for sure.... Id drive it till it dies, because its days are numbered......

I have a slip at the 2-3 shift, and before I bought it, they did a transmission flush (dont know about filter), and I feel confident about a fluid exchange...... I dont feel the need to cough up the money for a flush since the fluid is fairly new.......

Post by **cweberj30t** » Tue Nov 11, 2003 10:05 am

My transmission is strong as an ox for 80k but I hear so much about preventative maintenance I feel obligated to do something to keep it going. The fluid is in pretty good shape, but after 80k it does have some discoloration. I'm wondering if it is even worth touching since it isn't giving me any problems. I've all but ruled out the idea of a flush and am still contemplating doing the pan drop filter change and adding fluid. Sound good?

Post by **Jeff Williams** » Tue Nov 11, 2003 10:05 am

If you just "Have" to do something, I would agree that this is the most.

Don't be angry, if the car starts to slip between OD & D, at low RPM's afterwards.

I would get the filter and gasket from Scottsdale, get 5 quarts of transmission fluid, and shelf it, for the 120,000 mile servcie.

Post by **maxnix** » Tue Nov 11, 2003 10:05 am

cweberj30t wrote:My transmission is strong as an ox for 80k but I hear so much about preventative maintenance I feel obligated to do something to keep it going. The fluid is in pretty good shape, but after 80k it does have some discoloration. I'm wondering if it is even worth touching since it isn't giving me any problems. I've all but ruled out the idea of a flush and am still contemplating doing the pan drop filter change and adding fluid. Sound good?

No! If you read the previous posts, you will realize it's all about keeping the fluid pristine, and not allowing it to cook. Discoloration is its way of telling you it is breaking down.

Look, I have low miles (<60K) Qs, but they have all been flushed, and they all shift perfectly, and will for a long time (hoprfully). When the fluid is not bright pink, it is time to flush before it breaks down more. When is reddish brown, it is too late, and you are in a holding pattern. You cannot judge ATF condition by shifts until it is too late.

Post by **cweberj30t** » Tue Nov 11, 2003 10:05 am

I might have over empasized discoloration in my previous post. I just took a look at it and it looks bright pink with no debris. I'm worried if I do a flush, rings and seals might loosen up and cause more problems than help prolong the life of my transmission.

Post by **maxnix** » Tue Nov 11, 2003 10:05 am

Seals will only detiorate if you let your fluid overheat and/or detiorate, or filters become clogged.

When I did my last flush on a Sun machine, the garage owner was disappointed there was only a little bit of difference between the color of the fluids in the clear hoses. He is accustomed to seeing brown or black. I, on the other hand, was most happy to see so little difference.__________________Brian1995 Q45 & Q45t & 2000 Q45

Discover the power of the button!

Post by **Altiman94** » Tue Nov 11, 2003 10:05 am

Doing a flush of the system won't hur the car at all. I woudl like someone to explain to me WHY it would hurt the system to flush out contaminated fluid and replace with fresh fluid? If that holds true, why wouldn't it be the same for your engine?

Post by **natsoundup** » Tue Nov 11, 2003 10:05 am

I did a flush several months ago on my rebuilt 90Q transmission....it was the second flush of the rebuilt....at about 64k miles...the first was done about 30k..

up until then the transmission was working fine....the flush flushed out something...because it now slips in OD when you try to hit the pedal hard...

I have tried a lot of things to change it...and that's just the way it is..

However, I would do the same thing all over again.....

Post by **elwesso** » Tue Nov 11, 2003 10:05 am

A flush with solvents can move stuff around and possibly clog or dislodge something......

Post by **Altiman94** » Tue Nov 11, 2003 10:05 am

if it has solvents in it it would dislodge any clogs, it wouldn't clog or lodge itself anywhere.

Post by **springnr** » Tue Nov 11, 2003 10:05 am

Safest bet is to ease into the fluid change. A clogged filter is no good period so just drop the pan change the filter. About three quarts of transmission fluid will need replaced so just add 3 new quarts of Mobil 1 . Next oil change go ahead and drain the transmission pan too. Add three more quarts of Mobile 1.....Pretty soon most of your fluid will be Mobil 1 without shocking the system.

Post by **Jesda** » Tue Nov 11, 2003 10:05 am

I dont know what the hell to do now, Im so confused.

My 92 Q is on its second transmission, installed at about 50k under warranty. First owner, it got clogged and overheated.And the owner before me did all Mobil 1, but I dont know if he did a flush or just a refill, or if the filter was ever changed or the pan was ever dropped.

So I know1) I need to change the filter.2) I need to do a pan drop.3) Do I do a flush or just a refill? The fluid looks nice and clean.

I'm at 181k. Owned the car since 169k (April 03), and have done nothing with the transmission yet. Last owner had the car since 140k (Jan 2000).

What do I do? I dont want to destroy $3000 equipment and find myself stuck with the minivan.

-Jesda

Post by **natsoundup** » Tue Nov 11, 2003 10:05 am

anyone want to weigh in on draining the transmission pan every 3 months or 3k miles when you do your oil?

Then change the trans filter every 30k miles....and do away with the flush?

Post by **Jeff Williams** » Tue Nov 11, 2003 10:05 am

natsoundup wrote:anyone want to weigh in on draining the transmission pan every 3 months or 3k miles when you do your oil?

Then change the trans filter every 30k miles....and do away with the flush?

This is how I kept my '93 Accord running for 50,000 miles. I added a quart of CD-2 transmission conditioner, as well.

I have had luck using the Lucas treatment on the Q, so far.

Post by **elwesso** » Tue Nov 11, 2003 10:05 am

This is what I was thinking for the transmission fluid..... Flush it once, and then after that drain/refill every 6k (M1 or valvoline synthetic).... Replace filter at 30k....

Sounds good to me!!

To flush or not to flush

To flush or not to flush

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