Flash TCM Upgrade for 1990 Grand Voyager

My TCM is finned (not sure if original, bought van used) and, based on
posts, can be programmed. The van's transmission has been flawless
over the last 20,000 miles I have owned it. Now has 90,000 miles.
Can someone convince me to go ahead and take it in to get the upgrade
if it doesn't have it already? I have serious reservations about
letting anyone touch it, but a good argument might persuade....

 

If it's finned it probbaly has the latest software. THey can check it too.
Larry

 

if it's not broke don't fix it
the flashes are not availble anymore so a new one would be the ticket

 

Er...that doesn't sound right to me. According to Chrysler techs I know,
the flashes certainly *are* still available.

DS

 

i do believe alot of those flashes were dropped when they switched us from
mds2 to the new tech connect and i doubt there are any techs left that
remember how to use the old flash tools that were used to do so for the
early 90's controllers

 

Would a new one have the programming pre-installed? I think there
were two hardware upgrades after the original.

 

Based on 18-24-95, a 1990 AS GV would require TCM part no. 4796122 w/
pin 49 disconnected. It is the one with 4 heat sinks (there is
another later one with 7 apparently). It also says "Quick Learn
Procedure" is not applicable to pre-1992. I would want to know if I
buy a new TCM would it have the sofware and only require a swap w/o
going to the dealer? If it did need a flash, the TSB says a CH5500
Flash Program Kit and Scant Tool DRBIII CH6000 would be needed.

 

Several comments.

First, I agree with mic_canic about "if it's not broke, don't fix it."
If you take a vehicle that old into a dealer, you are just inviting
them to suggest a lot of other "urgently needed repairs" that might
end up costing more than the value of the vehicle.

Second, I have formed the general opinion that the TCM's (and the
SMEC's) were not able to be "flashed" (reprogrammed) until about 1995.
A recent purchase seems to back up that opinion.

I was recently able to purchase at a very reasonable price, a
remanufactured TCM. (It never hurts to have a spare.) According to
the ATSG handbook for the Chrysler A-604, the latest TCM part number
for 1989 to 1991 transmissions with the 3.0L engine is 4761846. My TCM
bears this part number and was rebuilt in 5/19/2000.

This TCM also contains a second, "authorized software update" sticker
that has the part number 04796121. Taking the cover off, I can see
through the clear potting compound, a large DIP chip that has been
marked in large numbers by hand "121" which corresponds to the last
three digits of the part number.

What I read into this is that the DIP chip is first programmed, then
installed into the circuit board, which is then installed into the TCM
housing.

Concerning TCM part numbers per the ATSG handbook.
Good for 1989 to 1991 model year.

5234623 - Early 1989
5234649 - Early 1989
5234678 - Early 1989
4557120 - During 1989
4557585 - During 1990
4672104 - For 1991
4572002 - During 1991
4672105 - During 1991
4728600 - For 3.0L
4728598 - For 3.3L
4761846 - Latest for 3.0L
4761847 - Latest for 3.3L

Also, the only mention in the ATSG handbook about programming is for
the 1993 TCM. All 1993 and later TCM's will have to have a pinion
factor programmed in order for the speedometer and transaxle to
function properly.

Hope this helps