Hi! I have a 2005 Mits Montero Ltd, 103K miles, sportronic trans, and 3.8L engine. Recently when I started the Monty after a few hours off (cold starts) when changing the shift lever from Pkng to Reverse the trans would take 5-10 seconds to engage, it would engage with a thump. If I would stop and change from Reverse to Drive it would do the same thing. And, same problem if changing from P to D, while trans was cold. After a couple of minutes trans is close to operating temp., and it would work normally. As an example, if I parked and turned off the vehicle for about 15 mins., when starting and moving the shift lever from P to D, or P to R, or R to D it would immediately hook up the gear. While underway the trans works fine, no slip, no missed gears, no jerks, etc. This only happens when starting the vehicle in the morning, or during shutdown periods of 1+ hours. As time progressed the symptom got worst, and the time the trans took to engage became longer to about 15-20 seconds, maybe a little longer. Oil level was checked, and it was OK.

An interesting thing is that when cold, as I applied more gas (accelerated) it would engage immediately doing a loud thump (engaging at higher RPM), sometimes a double engage (some quick-short slip, then fully engaged). My educated guess is that this happens because there is an increase in oil pressure that engages the gear.

Took the SUV to my mechanic (extremely reliable) for a trans oil/filter change, as I noticed it had never been done. The trans filter was dirty, there were some shavings, but not sufficient to get too worried, and 6 Qts. of the proper Mits trans oil was used ($10.00/Qt...Ouch!). He advised that the trans might be needing an overhaul, but that it was working fine now. It worked fine for a few days, then the problem started again, but at a lesser degree. My mechanic advised that I could use one of those "miracle additives" for trans, but that would only extend its life anywhere from 1 to 3 years, at the end I will have to overhaul. In Puerto Rico a product called "Médico Brujo" (Witch Doctor) is very popular, as it lubes valve seals and o-rings without using solvents, and helps a lot.

Here are my questions:

1. Any idea with what is the problem with my trans?

2. What additive would you recommend?

3. If you had this problem and fixed it properly, what was your repair bill? My best guess is between $2K and $2.5K.

My mechanic was a Ferrari, Alfa Romeo, and BMW trained tech, plus he has worked on my Audi, Jeep, road race car, and all other cars for over 10 yrs. He also hates working on auto trans, and he already said that if it is failing to take it somewhere else and that he doesn't recommend trans mechanics, as he doesn't know a single reliable one. So, since he doesn't have any economic interest, and so far he has always been fair and reliable; I must take his word, and will probable have to overhaul soon. But, right now I am using the truck daily to visit farms, so I cannot park it for awhile. Please, advise.

 

Great call using MM ATF. That is the only fluid you should put in your system IMHO.
The FSM calls for about 10-12 quarts of ATF for a proper flush.
The system holds 9 quarts. If the fella turning the wrench only used 6 quarts, then he did not perform a complete flush. If you saw some improvement after his service, I would be inclined to perform a complete flush.

Here is a link to the FSM- check out the section on "fluid replacement" :
http://www.pajero4x4.ru/piii/GR00006000-23Aa.pdf

Check if this link will ship MM ATF to your location (perhaps you can save some cash).
STM: FLUIDS | ENGINE OIL | TRANSMISSION | ATF | TRANSFER CASE

 

Thanks for the advise...I will talk to him to doing a complete flush. Great news! It will be a $100.00 to $120.00 flush, just for the trans fluid! When I bought the Monty a friend of mine told me that I might as well have purchased a Cayenne, Lexus GL. or LR3, now I know why; parts for this truck are not your typical Mits econo price.

Here in PR Mits is very popular, so when I went to Autozone and Pep Boys looking for the correct trans fluid the first thing the customer service adviser said was to go to the local MOPAR distributor, a Porsche parts dealer, or to a Mits dealer, as they are the only ones who carry the correct fluid. If not mistaken, it is the same oil Porsche uses on their tiptronic trans.

 

Forgot to mention, oil and additives are expensive to ship, as they are Hazmat.

 

When you buy OEM parts they are more expensive, however, they are built very stout and will last under severe conditions. IMHO they are worth it in some situations.

I've heard the same thing about Hazmat when shipping fluids, although this mob out of New Jersey shipped me my ATF with no sales tax to boot.

The transmission flush is a DIY service (another person in the driver's seat cranking the engine makes the process go much faster).

Here is a good link:

Gen3 : DIY - Auto Transmission fluid change - Pajero 4WD Club of Victoria Public Forum

 

Thanks for your advise...