2004R Shifting Question

[lbear]

I have a performance 2004R built with all the high performance parts (billet input shaft, HD clutches, etc). The vehicle is not driven much except when nice. I did a fluid change (Dexron Mercon) and added a Hughes Aluminum pan. I noticed that the 1-2 shift seems softer than it was before, almost a slight flare when at higher RPM's. The 2-3 is quick and firm as is the 3-4 shift.

The TV Cable is fully adjusted properly and is fully extended when at WOT. Trans temps are 160-180F max

What controls the 1-2 shift and if something is starting to go bad, what signs would be present?
Is Dexron Mercon the best fluid? (Former fluid was really good, red with no debris) (trans was built by Perfromance Trans in California - Bruce Toelle - Many years ago).

 

[gunzandgearz]

How many miles are on the unit one of the issues the people run into is transmission fluid is a cleaner basically a detergent and when you go in and put new fluid in a unit that has a lot of miles or is older it actually knocks all the sludge and debris loose and sometimes causes issues with the crap moving around and getting in the valve train and hanging up some of the valves,

 

[lbear]

About 15,000 miles. Street driven. Not drag raced.

Should I drain and refill with a different fluid?

 

[dsa87gn]

Did you use DexVI fluid by chance ?

I did this last summer switched from III to VI with a deep pan. I noticed softer 1/2 shifts too. At decent throttle no problems though
I'm about 1000 miles into it now and honestly it seems to have firmed back up some. I have a CK shift kit and the 1/2 is pretty harsh

 

[gunzandgearz]

Try adding two bottles of Platinum lubegard it has a friction modifier and will drop operating temps by up to 30 degrees you can get it at the local part store you might just have to ask for it or have them order it in ask Nick micale what he thinks about it I turned him on to it and he loves it stuff works great

 

[dank GN]

The TV cable doesn’t control the shifts it controls the line pressure . There is a governor in the trans and they are notorious for loosing these lil balls that are in there . Anyway you can try taking 1 click back on the TV cable and see if that helps your issue.

 

[lbear]

Did you use DexVI fluid by chance ?

I did this last summer switched from III to VI with a deep pan. I noticed softer 1/2 shifts too. At decent throttle no problems though
I'm about 1000 miles into it now and honestly it seems to have firmed back up some. I have a CK shift kit and the 1/2 is pretty harsh

I used Valvoline Dex/Merc "for vehicles requiring Dexron III/Mercon - GM pre-2006 models - helps protect against wear & provides smooth shift performance" (as per label on jug)

 

[lbear]

Try adding two bottles of Platinum lubegard it has a friction modifier and will drop operating temps by up to 30 degrees you can get it at the local part store you might just have to ask for it or have them order it in ask Nick micale what he thinks about it I turned him on to it and he loves it stuff works great

I noticed Amazon sells it for like $10 per bottle. Pour 2 bottles in? No need to remove trans fluid so as to not overfill?

 

[lbear]

When in 1st gear. What controls the 1-2 shift? Is it the band?

 

[dank GN]

Go to Walmart and get there brand dextron 6 it legally has to have all the same stuff in it to be called dex 6 and it’s 6$ a quart

 

[gunzandgearz]

I noticed Amazon sells it for like $10 per bottle. Pour 2 bottles in? No need to remove trans fluid so as to not overfill?

Yes it is the band that comes on when it makes the 1 to 2 Shift and that's a pretty good price through Amazon just get two bottles and pour it in its not enough to affect the fill levels

 

[gunzandgearz]

The TV cable doesn’t control the shifts it controls the line pressure . There is a governor in the trans and they are notorious for loosing these lil balls that are in there . Anyway you can try taking 1 click back on the TV cable and see if that helps your issue.

Not trying to call you out or anything on this but the line pressure actually does play a part in the shift timing as it works in conjunction with the governor pressure to control the shift timing if you disconnect the TV cable watch how fast the shift happens or if you pull it out as far as it will go the shift timing be a lot later so it does play A Part

 

[dank GN]

Not trying to call you out or anything on this but the line pressure actually does play a part in the shift timing as it works in conjunction with the governor pressure to control the shift timing if you disconnect the TV cable watch how fast the shift happens or if you pull it out as far as it will go the shift timing be a lot later so it does play A Part

Yes I understand that but it isn’t the only thing . The governor in the trans is actually what dictates the shift points .

 

[lbear]

Yes it is the band that comes on when it makes the 1 to 2 Shift and that's a pretty good price through Amazon just get two bottles and pour it in its not enough to affect the fill levels

What does that fluid do/help with?

 

[lbear]

So if the band controls the 1-2 shift. Could the band be going out? How would one tell if the band is starting to go bad?

I believe Bruce used Kevlar bands if I am not mistaken.

 

[77 cruiser]

Pry in on the servo cover & see how far it moves, might have broken band lug or anchor.

 

[gunzandgearz]

Yes I understand that but it isn’t the only thing . The governor in the trans is actually what dictates the shift points .

Well how it works is the governor pressure goes to the back side of the shift valve and works in conjunction with spring pressure behind the valve and the line pressure is in front of the valve so the line pressure is low like the cable is disconnected it will change the shift points there has to be a balance there in other words if the cable is not adjusted correctly the balance pressures won't be right so if you disconnect the cable or it's pull out too far then the pressures won't be correct that's why I was saying for a test you can disconnect the TV cable and drive it and watch how fast it shifts or pull it out as far as you can and it will shift late kind of like disconnecting the vacuum modulator on a modulated transmission basically the cable is doing the same thing as a vacuum modulator it determines how much engine load is being put to the transmission vacuum modulator will increase the pressure as you stomp on it because manifold vacuum goes down the cable operates off throttle opening the further the throttle open the more load

 

[gunzandgearz]

What does that fluid do/help with?

It is a friction modifier in other words it makes the clutches and bands more grippy in layman's terms I'm not saying this is your issue but when I troubleshoot something I look at it as was it self induced or was this a problem before you did what you did and that doesn't sound like the case it is actually very odd if the fluid level is correct it shouldn't be acting up at all but I will say this if you stomp on it and it makes a good one to shift the band is doing its job as far as going to a synthetic fluid my personal opinion is I don't like it they're too slick as a matter of fact if you buy a new car even with a limited slip clutch style differential the manufacturer will tell you not to put synthetic fluid in them because they will burn the clutches because the fluid is just too slick again this is my opinion others might have a different viewpoint on it but if the manufacturers won't put it in their brand newposi units with clutch Style posis then that should tell you something it works the same for transmissions especially the old school units

 

[gunzandgearz]

So if the band controls the 1-2 shift. Could the band be going out? How would one tell if the band is starting to go bad?

I believe Bruce used Kevlar bands if I am not mistaken.

yes I just talked to Bruce the other day as a matter of fact and I know those are good bands if it were me I would put that fluid in it and drive it see how it acts after a couple of weeks it might clean itself up if not one thing for sure it will show you the problem eventually you might inbox Bruce and see what he thinks he built tons of these units

 

[gunzandgearz]

Well how it works is the governor pressure goes to the back side of the shift valve and works in conjunction with spring pressure behind the valve and the line pressure is in front of the valve so the line pressure is low like the cable is disconnected it will change the shift points there has to be a balance there in other words if the cable is not adjusted correctly the balance pressures won't be right so if you disconnect the cable or it's pull out too far then the pressures won't be correct that's why I was saying for a test you can disconnect the TV cable and drive it and watch how fast it shifts or pull it out as far as you can and it will shift late kind of like disconnecting the vacuum modulator on a modulated transmission basically the cable is doing the same thing as a vacuum modulator it determines how much engine load is being put to the transmission vacuum modulator will increase the pressure as you stomp on it because manifold vacuum goes down the cable operates off throttle opening the further the throttle open the more load

Before I get called out the pressures are opposite Governor pressure is on the front side of the valve and line pressure is on the backside with the spring pressure just thought I would clear that up as I just re-read my statement