i keep seeing in this group "do not use DextronIII" why? dextron seems to be compatible to domestic and import cars, it even says on my dipstick to use DextronII(DexIII is a sub for DexII). anyone, what's going to happen if i use DexIII and why? thanks Ilia
Its not good for the trans. I use atf+2/7176 fluid 9or whatever it is)
ATF+4 buy at autozone
I assume you have the Ultradrive transmission since you added "OD" in the subject. This transmission began life in 1989. If so, you should not use Dexron at all.
If you actually have the three-speed automatic, then Dexron II is fine.
The proper fluid for the Ultradrive is Type 7176, also known as ATF+3.
A misprint in owner's manuals and transmission fluid dipsticks in early models indicated the use of Dexron II transmission fluid in the event the required fluid was not available. However, Dexron does not provide the correct friction characteristics for proper operation of the transmission. It can easily result in malfunction, causing transmission shuddering, often putting the computer into the "limp-home" mode, under which the transmission will not shift beyond second gear. Or it can result in complete failure of the unit.
wow this is prity serious, you can tell right, i just filled my trans with dex3 before i found this google group. shaiza Yes mine is with Overdrive, automatic (P-R-N-OD-D-L), this is 3 speed right? Actually something i have to note. i'm not sure what the previous owner used, but the trans did shudder a bit and was operating poorly, on a hill would not downshift if had no power, insted it would stick to higher gear and slow down as a result. anyway it felt like it was in need of fluid change.
I changed it about 2Kkm ago, used Dex3. Now it is much better, does not chadder, holds the gears well and shifts smoothly up and down depending on the need of power. Now that i found this comment i'm worried, you(marcus) mentioned that dex2 is good for my trans. How can i find out which trans i have(where is the stamp on the trans?), and if Dex is compatible for my trans?
thanks for all your replies, i greatly appriciate it. Ilia
Marcus wrote:
On any modern automobile, if you have "overdrive", then by definition you have at least a four-speed automatic (and on the latest models, it might be five, six or seven speeds).
Also by definition, the "Ultradrive" is a four-speed automatic.
You should NOT use the Dexron. Unfortunately, even today there are many mechanics who put Dexron III/Mercon into everything.
I recommend that you change the fluid again to get rid of the Dexron to get ATF+3 in it. If you can make sure the torque converter and transmission cooler lines are cleared as well, that would be best to avoid contamination of the new fluid with Dexron.
See if we get some other opinions on the subject.
ATF+3 is a readily available mineral oil-based ATF that is suitable in any application calling for ATF PLUS® , ATF+2® , or a Type 7176® fluid.
ATF+4 is a synthetic fluid that has a remarkable improvement in fluid life, retaining "as new" viscosity and anti-shudder to 100,000 miles.
Dexron itself is the General Motors-specified fluid from far back in automotive history. While it was once the standard for all American autos, that time has long passed, with Ford settling on Mercon and Chrysler on ATF+3 (and now ATF+4); other manufacturers also require their own fluids.
Hope this helps?
There is a TSB on ATF+4 and most Chryslers new or old use ATF+4 it replaces ATF+1-3, also check out the link. ATF+4 is sold at all the auto parts now, Valvoline makes it and cheaper than the dealer.
Also this link,
A good link for basic tranny trouble shooting.
I was a little unsure about ATF+4 in the oldest 4-speeds; good to hear that ATF+4 is fine. It's a big improvement over ATF+3 for longevity.
Great links there! Particularly important are these two quotes from the Allpar link:
When you change your transmission fluid, always use the recommended (in the manual) fluid. (1989-91 owners, ignore the manual and use ATF+3). All Chrysler four-speed automatic transmissions* are very sensitive to the quality of the transmission fluid. Only use the ATF+[3 or 4] in these transmissions. Do not use Dexron or Mercon.
Dexron is not a universal fluid. Chrysler four-speed automatics only use ATF+3 (ATF+4 for newer vehicles), regardless of what the dipstick or owner's manual says.
Do not use Dexron with an additive. Richard Widman passed us an extensive report from reputable gas company Chevron, which compared ATF+3 fluid with Dexron plus various additives. They found that neither of two major brands matched ATF+3's performance specs.
thanks marcus, coasty and all rest. you guys are great. here is a recap. just after i posted the question here, my trans got stuck in 3rd gear and would not switch to 4th. by the way found out mine is a 4 gear 604 trans, by looking at the trans filter at canadian tire, the parts clerks there are no help at all. So Overdrive makes it a 4 gear trans. anyways, thanks to you guys i figured that the fluid is what caused this. thanged it and the filter and gasket, after first two rides didn't help it was still stuck at 3rd gear. i cleaned the connector aswell(read it somewhere here that that is a nother problem spot, because it collects water and deteriorate the connection), went away for an hour, when came back, presto, the trans is back to good old self, even better than was before.
i can't believe that the fluid can cause such a damage, and on the other hand fix it so easily.
thanks guys you are the best
Ilia
ldenn2 wrote:
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