NAG1 Transmission Fluid Change

sikwan

06 T1N Can
I just attempted a fluid change on a 2004 with 348000. I had been having troubles with shifting from 2nd to 3rd. when the transmission tried to shift, it would go into 'neutral' before shifting. if I timed it just right I could just barely let off the pedal at the right rpms and it would shift a little smoother and I would continue driving. a few weeks ago it completely failed to go into 3rd, and I had to coast off the highway. I let it sit for a few minutes and got back home ok. I read the code, and it was incorrect gear ratio.
The shift from 2nd to 3rd, for me, when I'm taking it easy will normally cause a rumble strip noise right around 20mph. To avoid this , I would drive a little more aggressively (with more pedal to the metal) so that the shift happens above 20mph.

I'm wondering if it's similar but more drastic in your case. For me, if it's 348000 and you do not have a history of the van, I would plan on having it remanufactured or having it replaced with one. Fluid is expensive and would be a waste as it sounds like it will only be a bandaid.

What was the fluid like when you drain it? How was the old filter?

Sometimes at the mileage, it would have been better to top it off because a drain removes the friction material that has come off and are floating in the fluid. But, it doesn't sound like it since it's faster and smoother now.
 

gogobrent

New member
The shift from 2nd to 3rd, for me, when I'm taking it easy will normally cause a rumble strip noise right around 20mph. To avoid this , I would drive a little more aggressively (with more pedal to the metal) so that the shift happens above 20mph.

I'm wondering if it's similar but more drastic in your case. For me, if it's 348000 and you do not have a history of the van, I would plan on having it remanufactured or having it replaced with one. Fluid is expensive and would be a waste as it sounds like it will only be a bandaid.

What was the fluid like when you drain it? How was the old filter?

Sometimes at the mileage, it would have been better to top it off because a drain removes the friction material that has come off and are floating in the fluid. But, it doesn't sound like it since it's faster and smoother now.
I just took it for a test drive after letting it sit over night. the error codes are gone and the shifter is behaving normally now. fluid levels were checked and reading exactly at the lower line on the 80 side.

I was actually surprised at the cleanliness of the pan and electrical components. the magnet had some goo on it and a little on the sensors but no large amount of metal chunks anywhere.

so my uncles business bought the van new. it was serviced by the shop next door, and judging by the drain bolt on the torque convertor, maybe not that well. the engine only has less than150k on it, as it was swapped 7 or so years ago.

on my second drive it did seem a little more aggressive than im used to. the shift flare is still there, but it was a fraction of what it was before. I do wish I would have been able to drain the torque convertor and im wondering now if I should have just replaced the conductor plate. it seems to be original. I cleaned it thoroughly with electronics cleaner.

im going to hold off on dropping the pan again, as everything seems to be working at least better than it did. im still curious as to whether or not I connected the selector valve right, but it seems to be shifting fine, so ill just monitor for a few days and see what happens.
 

Protege91

New member
Transmission in "N" insert a screwdriver (rectangular inspection opening) and turn TC until you see the drainplug,TC will turn very easy.
Uh, where are you putting this screwdriver? I just tried this technique and the TC would not turn. Note, engine and trans were cold at the time. I’m experimenting a dry run before I do it for real.
 

sikwan

06 T1N Can
Uh, where are you putting this screwdriver? I just tried this technique and the TC would not turn. Note, engine and trans were cold at the time. I’m experimenting a dry run before I do it for real.
The screwdriver slot is in the cab, right below the letter "D." He's putting the transmission in Neutral by inserting a screwdriver into the slot.
 

Bill B.

Member
I’ve noticed a similar shifting irregularity myself. It seems to require an excessive RPM before upshifting 2nd to 3rd.
There’s also an irregularity after the upshift from 1st to 2nd. Unlike the above 2nd engages right away but as RPM increases just after the transition you can feel a slight secondary up shift. It’s not as distinct but it’s definitely there. It’s as if it hadn’t fully engaged or there is a split 2nd gear ratio which I know sounds ridiculous but it’s not present anywhere but 2nd gear.
I’m just over 40k on a 2006 2500 but like you I changed transmission fluid but both issues are still present. I did remember to disconnect the battery before the procedure, drained the torque converter, changed filters, and followed all the refill procedures(as per sikwan’s 2008 write up) but one. I refilled with 7 quarts(6.62 litres) and thought I would need more. Sikwan specifies 8 quarts(7.57 litres) for the NAG1 which would mean we’re both underfilled. However, after the shift procedure, a warm up drive, and a few miles on the freeway the dipstick indicates my level is spot on with the upper mark, at the Indicated temperature, while the engine is running, and selector is in ‘Park’. But I should check the level again to make sure I followed all the rules. Procedure Diligence Matters
I reckon. I need to affirm the drain spec refill. 1.5 liters is a significant difference
Note: As I recall there is a step in the procedure(perhaps overlooked by the OA) which requires the selector to be used and the trick you mentioned is described in the owners manual so in case someone’s wondering there’s no need worry about damaging the shift selector as long as it’s done correctly.
 

Aqua Puttana

Poly - Thread Finder
The dipstick level being correct with a "hot" engine determines the proper sump level. Any comments about quarts or liters involved in a fluid change are general guidelines at best.

Not that anyone asked...

If you are an eggshell on the throttle pedal type of driver I recommend some spirited driving on occasion. Power up freeway on ramps to get some good hard(er) shifts. I drive gently. The times that my 2004 has displayed slightly different shifting or light flare I have done some harder driving for a time. It has always made the transmission return to my "normal".

The above said, obviously if there is something mechanically or electronically wrong with your transmission hard driving won't help. It is cheap and easy to try though.

:2cents: vic
 

Bill B.

Member
The dipstick level being correct with a "hot" engine determines the proper sump level. Any comments about quarts or liters involved in a fluid change are general guidelines at best.

Not that anyone asked...

If you are an eggshell on the throttle pedal type of driver I recommend some spirited driving on occasion. Power up freeway on ramps to get some good hard(er) shifts. I drive gently. The times that my 2004 has displayed slightly different shifting or light flare I have done some harder driving for a time. It has always made the transmission return to my "normal".

The above said, obviously if there is something mechanically or electronically wrong with your transmission hard driving won't help. It is cheap and easy to try though.

:2cents: vic
That makes sense Vic. I’ll give it a try. I baby this beast too much.
 

Protege91

New member
The screwdriver slot is in the cab, right below the letter "D." He's putting the transmission in Neutral by inserting a screwdriver into the slot.
I read that to mean something different.
"Transmission in "N" insert a screwdriver (rectangular inspection opening) and turn TC until you see the drainplug,TC will turn very easy."
I read this to mean After putting the transmission in "N" (however you choose to make that happen), then open the TC inspection plugs and insert the screwdriver in some magic slot of the TC to turn it, as an alternative to rotating the crankshaft.

With my transmission in N, I'm not able to turn my TC. Should it be easy to turn? Note that I was doing a dry run with the engine/transmission cold (60 or 70 degrees F).
 

Aqua Puttana

Poly - Thread Finder
...

With my transmission in N, I'm not able to turn my TC. Should it be easy to turn? Note that I was doing a dry run with the engine/transmission cold (60 or 70 degrees F).
:idunno:

Both my 2004 and 2006 turn easily using a socket on the crankshaft. I never take the gearshift out of park when I rotate the engine to access the TC drain plug.

vic
 
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Grouser

Active member
Just a note,
The manual talks about a different shift pattern for cold verses hot engine. It will hold it in a gear a bit longer to achieve higher rpm to build up heat in a cold engine faster
 

Protege91

New member
:idunno:

Both my 2004 and 2006 turn easily using a socket on the crankshaft. I never take the gearshift out of park when I rotate the engine to access the TC drain plug.

vic
I still didn't word my question very well. I thought he was saying you can skip rotating the engine to rotate the TC. As if you could just hand-turn the TC itself by pushing a screwdriver against the TC at some angle.

I'm just trying to avoid finding a socket/extension that will fit the crankshaft since I full-time in my RV and don't want to accumulate more spare parts. :)
 

Aqua Puttana

Poly - Thread Finder
I still didn't word my question very well. I thought he was saying you can skip rotating the engine to rotate the TC. As if you could just hand-turn the TC itself by pushing a screwdriver against the TC at some angle.

I'm just trying to avoid finding a socket/extension that will fit the crankshaft since I full-time in my RV and don't want to accumulate more spare parts. :)
Unless you get stupid you really can't hurt the TC by levering it around. My suggestion would be to wrap the tip of lever aka screwdriver with a decent layer of duct tape. That will help to grip the outer surface of the TC and also reduce the chances of damage... however slight the potential for damage might be.
:2cents: vic
 

Little Harold

New member
Thanks for the post! I will attempt this service over the weekend on 2005 T1N with 300K km.
-Is it absolutely necessary to buy the dipstick?
Thanks !
Harold
 

Bill B.

Member
In my opinion there’s no valid reason to avoid buying a dipstick and doing the procedure as directed. That said, is it absolutely necessary to use your engine oil dipstick or for that matter check any fluid level after changing it? No, but the potential consequences outweigh any reason to do otherwise.
 

Little Harold

New member
Thanks Bill! I will go ahead and order one. I am confused as to the volume of ATF 134 needed with Torq Converter drained. Some videos say 5 QTs, others say 8 QTs. And for some reason I can't find the Shell ATF 134 in Canada? Could you help me with sourcing the right amount of an approved fluid? Much obliged, Harold
 

Little Harold

New member

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