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Possible tranz troubles

2K views 27 replies 5 participants last post by  Jasen 
#1 ·
This morning on the freeway it felt sort of like the tranny might have slipped in and out of gear a couple times. Once getting on to the the surface streets it did it again. Pulling away from a stop sign and just as it was time to shift into 2nd it did it again, felt like it was slipping back and forth between 1st. and 2nd. If I played the throttle I could keep it doing it. I'm thinking on the freeway it was slipping between 3rd.- 4th.
It was fine until it got up to temp. On the way home today it only barley did it at all shift points under light acceleration.
I checked the fluid at work and it's at the proper level but is a little brown.
I still haven't fixed my EVAP problem :oops: But it generally runs pretty good except for the 13 mpg.
So I don't know if it's the tranny or if it's getting improper signals from the ECM.
Any idea's?

97 AWD with 179K and about 100K on the tranny.
 
#3 ·
about 100K on the tranz and 179K on the motor.

I just made a 6 mile run to the store, and it didn't do it.
 
#4 ·
Jasen said:
about 100K on the tranz and 179K on the motor.

I just made a 6 mile run to the store, and it didn't do it.
Last service? I would go with a pan drop, filter change, top off fluid, and make sure you leave enough room for a bottle of Seafoam Trans Tuneup. It"s Good Stuff.
 
#5 ·
I picked the tranny up at the J/Y. It had 86K on it. I had it serviced when the shop put it in about 15K ago.
I was thinking of new filter and fluid. But just wondering about the tranz being sent improper signals from the ECM.
 
#6 ·
Jasen said:
tranz being sent improper signals from the ECM.
Does the fluid smell burned? Check for codes? Plenty of transmission codes/data available through scan tool. Once you have that info, you can get a ATSG/ manual for your unit and then determine if it is something that you can/want to do or take it to the shop. The FSM has some info in it and is a good read anyway. The FSM 'trans' manual is available as well. Diagnose the problem first and save the new fluid and filter for when you figure out the problem.
 
#8 ·
The mileage was good after the tranz swap. The EVAp issue that I still haven't fixed :oops: is when the mileage dropped. According to the color chart it's border line and smells fine.
I'll do a fluid filter sunday and barrow the parts stores code reader and see if anything comes up.

It only did it a little this AM, and nothing tonight and I had an appt. after work which doubled my usual drive home.
 
#9 ·
So this AM I head out, the SES light never comes on. It's been on for over a month due to the EVAP issue. The van ran better then it has been and no sign of stumbling during shifts? Still going to change the filter sunday.
 
#13 ·
#19 ·
Exactly what I'm thinking. Thought it might have been an ECM or PCM issue :shrug:
Still the tranz fluid could use a changing.
 
#21 ·
When you get a scanner plugged in, make sure you record all codes and freeze frame data. This may be the only chance we get for a while. My only concern on the fluid is we don't add anything else to the mix until we know what the problem is.
 
#22 ·
OK, smack me now. Thinking of going to Jiff Lube and getting the tranny flushed. I don't have the equip to dump out the converter.
After I pull any codes
 
#24 ·
Ok, scanned it and still getting the P0440, now I'm also getting P1300 igniter circuit/random misfire and P1100 MAF intermittent. Could these issues cause the shifting problems, maybe causing an inconsistent or conflicting signal to be sent to the tranz?
The tranz acted up just a tad today during light acceleration going from 1-2 and 2-3, but 3-4 is smooth. When in heavy traffic, it seems to kind of hunt for the next gear, but under moderate to heavy accel. it shifts just fine, well maybe a little hard like a lite shift kit.
 
#25 ·
Do you remember what brand of scanner was used? Those last two codes seem generic. Do you have a FSM for your van? Got a test light and a meter? I'm willing to spend some time on this but I need to know if you want to diagnose per factory troubleshooting. On the P0440, what have you tried or replaced?
 
#26 ·
It was the Auto Xray 6000 scanner, found the same one as the auto parts store on Amazon.

Haven't touched the P0440 yet and I do have FSM's which I couldn't find the 1100 or the 1300 DTC's in, had to look them up online. I'm going to do some reading in the FSM tonight and see what I come up with.
The tranz issue is seeming to be intermittent. I wonder if there just some sludge fouling things up from time to time.
 
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