[MC's 93]

I have heard it said that if you have a car which has never had the tranny fluid changed in let's say 100K miles, it's probably better not to change the fluid any more.

Do you agree or disagree? and why?

The reason I ask is that I have not changed the tranny fluid since I purchased the car at 50K. My car now has 135K and I'm sot sure if I should or should not replace fluids. Please read below:

93 Intrepid 3.3L 135,000 miles
Annoying surging during downshifting between 2nd and 1st gear when coming to a slow stop.
Near 95K the tranny got overheated during heavy stop & go traffic. I didn't know it until it the traffic cleared and I stepped on the gas and went nowhere. The tranny would not get out of 2nd gear, so I pulled over and shut the car off. After about an hour it cooled off and it was fine. Took the car into Dodge, ran diags on the computer - advised that I need to replace the tranny - $2400, I don't think so - I left it the way it was. The dealer said it wasn't even worth changing the filter and fluids. That was 40K miles ago - car is running good.

- MC

 

[p3]

As I found out the hard way, alot of dealers will try to get you to go the expensive route. As far as I know, I thought tranny fluid was suppose to be flushed and filled every 25,000-30,000 miles. If you are worried about future overheats, you could look into a, "one size fits all" if you will, tranny cooler.

 

[1mz-fe]

i agree, i'd go ahead and have it flushed and refilled with a new filter installed. a tranny cooler wouldn't be a bad investment - they're cheap, 50-60 bucks, and from what i've heard, easy to install. talk to SoBL64 about this project, he has done it.

 

[Maverick9110E]

can u change the trans fluid and flush it like at home in a few hours or do u have to take it somewhere else to get it done?

 

[viprman]

The reason that you aren't supposed to replace the tranny fluid on a car that has gone over 70,000 miles without it done is because the fluid breaks down and actually bonds to the parts of the transmission. It coats the parts with a "varnish" that once intact becomes an integral part of the tranny. If you replace the fluid you risk upsetting this balance and causing shifting and drivability problems.

If I were you, I would consult a tranny specialty shop (Aamco?) and ask them this question. They may offer a service that cleans off the parts and makes them good as new. May be quite expensive, I don't know the price.

 

[gr8crash]

i wouldn't really go to a "chain" tranny place, only cuz they are in the buisness to make money, and i have not had great sucess or heard many good stories of chain places. look around for a local or performance tranny shop. get there opion. guys that have been around for along time, they tend to do better work cuz there reputation is built on word of mouth, so they want to do a good job since they know it will prob get them more. chain shops could care less if they piss you off, they stil get customers al teh time.

 

[MC's 93]

I'm don't trust those transmission "chains" either. I once tok my Nissan to Aamco to have a tranny rebuilt and I was not impressed with the service. Unfortunately I don't know any good local shops where I can go for service but I'll look around.

Is there any tests that can be done to the tranny fluid to see if it's still good. If I knew that the fluid was still good from a test I would then have it drained and have the filter replaced. I'm concerned that the tranny fluid may have already broken down as "Viprman" described which then would be a bigger problem. I'm thinking of a test such as the test for antifreeze.

- MC

 

[99300mricva]

Other than looking at the fluid for burnt smell and brown color, both which would indicate it should be changed, the only other option is to send a sample off to a lab for oil analysis. Oil Analysts Inc. and other do that, but it's better to just change the fluid every 25K or use a good synthetic transmission fluid. I use Amsoil and it lasts typically 3 times or more that of regular fluid. It's ATF+4 certified and it runs cooler due to less friction. I have run this fluid for more than 100K miles in other vehicles with no problems. My other family vehicles are newer and were changed when new and still have the fluid a few years later with no problems. It can be a fill for life fluid according to Amsoil, and so far I'm doing just that. Right now, I've had 43K trouble free miles in my 300m, 77K in my truck, and 80k in my dad's Jeep. I tow a heavy race car trailer regularly in my truck too. To me there is no better fluid on the market. http://www.amsoil.com/products/atf.html

 

[MC's 93]

I checked the fluid and it doesn't look brown nor does it smell burnt. The color is reddish and it seems to be ok on visual inspection. Perhaps it's not too late to change it.

99300mricva - thanks for the tip on the "AMSOIL" synth fluid. I checked the website and it looks like it's $8 a quart. I wonder if the local Jiffy lube place will allow me to bring in my own tranny fluid? I'll make some calls.

Maverick9110E - here's a how-to guide to changing the fluid yourself which I found on this site:

http://www.amsoil.com/faqs/faq8.htm

-MC

 

[99300mricva]

Yeah the fluid is expensive, but you only gotta buy it once. Plus it's really no more expensive than ATF+4 from Mopar.

I've used that fluid change method in the past with success. This uses the transmission fluid pump to exchange all the fluid. You just keep pouring in new fluid in the dipstick tube until you've put more in than it can hold, say 15 qts in a 12 qt system. That way you know you've purged the lines, cooler, and torque converter. You should still drop the pan and change that filter though and add back the 5 qts or so you lose before you start the pumping method.

On my 300, there wasn't enough room to get my big hand up behind the radiator to release the cooling line. I went to my local transmission shop and had them do a power flush instead. I brought them 15 qts and they used it all.

Those two options should work for you.

 

[MC's 93]

Ok, I'll probably make a decision on this next week because I don't want to lose the tranny anytime soon. I'll let you know how it turns out.

- MC