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Discussion Starter · #61 ·
I was able to add an additional ~1.5qts of fluid yesterday above the OEM fill level. However, I have one final mod to make. I don't like the venting on the top of the trans so I ran an 11mm hose towards the back of the car to incorporate a catch can. My setup wasn't spitting fluid from the vent, but the general emission of trans vapor is enough to cover the trans over time.

I made a simple open can that I will fill with stainless dish scrubbers and has two vents on top. I will have a drain line running to a petcock that I can get access without having to remove the panels. It's not often I get to use the work petcock.

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A guy on the forum asked me about a catch can setup GTR Ronald I think it was. I remember a while back that Shawn Hayes told me it was usually track guys that used these. But of course just as good for stopping leakage.
 

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Discussion Starter · #63 ·
A guy on the forum asked me about a catch can setup GTR Ronald I think it was. I remember a while back that Shawn Hayes told me it was usually track guys that used these. But of course just as good for stopping leakage.
It is my understanding they are used for racing conditions since they are typically over filled by as much as 4 extra quarts. In my case I just don't want the top of the trans getting covered due to the vent. Since I can fabricate everything myself in the garage, other than my time there is no substantial cost. In the case of this catch can I just put it together with stuff I had laying around.

I managed to get 6 stainless steel scrubbers in the can before welding shut. I'll fabricate the mount and install the catch can tomorrow so I can put back on the under trays.

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It is my understanding they are used for racing conditions since they are typically over filled by as much as 4 extra quarts. In my case I just don't want the top of the trans getting covered due to the vent. Since I can fabricate everything myself in the garage, other than my time there is no substantial cost. In the case of this catch can I just put it together with stuff I had laying around.

I managed to get 6 stainless steel scrubbers in the can before welding shut. I'll fabricate the mount and install the catch can tomorrow so I can put back on the under trays.

View attachment 399823
Where does the OEM drip line from the breather end? I can see on the exploded view it drops down on the RHS looking from the rear of the car. Not a good solution if it coats the trans in oil it could be mistaken for a leak, I think that`s what happened to GTR Ronald if the name is correct.
On my Buschur catch can I installed a small ball valve I had at home instead of the petcock worked very well. The drain was a little difficult to get at so the ball valve made it very easy to open and shut.
 

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Discussion Starter · #66 ·
Where does the OEM drip line from the breather end? I can see on the exploded view it drops down on the RHS looking from the rear of the car. Not a good solution if it coats the trans in oil it could be mistaken for a leak, I think that`s what happened to GTR Ronald if the name is correct.
On my Buschur catch can I installed a small ball valve I had at home instead of the petcock worked very well. The drain was a little difficult to get at so the ball valve made it very easy to open and shut.
On my CBA there was nothing connecting to the vent.

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Discussion Starter · #67 ·
I haven't figured out how i'm going to position my petcock:rolleyes:, but my plan is to start putting on the under tray's back on and perhaps mount it on the panel itself somewhere I have access to the lever controlling the ball valve. It is important the ball valve and petcock work together.:unsure:

Once this is done I will start playing with the TCM tune to raise the line pressure from ~16.5bar to 21-22bar.

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Yes, you can clearly see the tube on the diff breather but none on the trans breather? Seems a little strange maybe I was confusing the two?
 

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Discussion Starter · #70 · (Edited)
One step forward, two steps back. This is the current state of affairs for the rebuild, but not to worry it is nothing major.

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I decided to put more miles on the car Thursday before putting back on the panels below the car. However, in the process I noticed there was transmission fluid leaking, but I couldn't determine where it was leaking since the car was on ramps and I was laying on my back. I put the car on the lift and quickly discovered the leak was from the FWD shaft seal, which is the one I replaced with the new Dodson seal.

I decided to remove the driveshaft to make sure the nut on the flange was still tight since I felt some in/out play on the flange. Before removing the nut I wanted to check the ETS preload and let's just say it was significantly lower than 18Nm, but I will address that in another post. Anyway, backed off the nut and then hit it back with the impact wrench to ensure it was good and tight.

I pulled the front cover and when I removed the FWD driveshaft flange I notice a bunch of burnt and torn rubber on the inside of the flange as well as around the Dodson seal. If you look at the picture below, you can see that I set the Dodson seal depth to where the top of the seal was even with the taper on the front case. At this point the seal can actually be pressed into the front case another 0.110" before it bottoms out. You can actually see some of the torn and burnt rubber around the seal and this was taken after I wiped most of it out.

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Although hard to see from the picture above, the seal has a lip that extends out towards the driveshaft flange and this lip was rubbing on the driveshaft flange and heating up the seal. I suspect a combination of physical contact and heat caused the seal to quickly fail. If you look at the picture below you can see where the Dodson seal was wearing against the driveshaft flange and when I pulled this off the entire area was covered in melted rubber. You can also see the wear mark of the OEM seal, which was just about in the middle of the shaft.

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The pic below gives a better perspective of just how close the Dodson seal is to the end of the shaft. This is how the Dodson seal was position with the lip of the seal pressing against the driveshaft flange. In this position the seal is 0.105" away from the end of the shaft where the taper begins. However, as you saw in a previous picture, I can actually press the seal another 0.110" before it bottoms out. So basically, when you press the Dodson seal all the way down the actual seal area is at the very edge of the shaft as opposed to the OEM, which seals in in the middle. I'm not saying the Dodson seal doesn't work because it has been used successfully for many years, but i'm not impressed with how close it seals towards the edge of the flange with no room to spare.

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I pulled the numbers off the Dodson seal and it lists the following...
NJ-575
38332-21100 4412

If the seal has the markings NJ ###, that means it is a seal manufactured by Timken under the brand name "National Seal."

You can use either of those numbers to find the seal online and when you look up the part number in the Timken catalog you get Part # 1173. So the $50 Dodson seal is a National Seal Part # 1173 and you can purchase at Advance Auto for $12.49, which explains why it fits like crap.
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I went ahead and ordered a new OEM seal from Nissan for $19.50, which will arrive Tuesday. My OEM seal had zero issues and actually fit correctly.
Nissan Part# 38189-JF00A
 

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Discussion Starter · #71 · (Edited)
There was a member that posted his DIY ETS rebuild thread and it can be found at the link below. He took a different approach and unbolted the gear from the bottom of the ETS to fill the unit with fluid. Using this approach you can screw down the cap and then fill from the bottom without pressurizing the ETS.
FWD rebuild procedure

I ended up screwing down the cap all the way and then adding the fluid from the bottom through the bearings as you can see from the picture below. My only concern when doing this is that you are not necessarily soaking all of the frictions properly before you set the ETS preload. If you are using brand new clutches then you MUST soak then for several hours prior to installing in the ETS and make sure you save the fluid if you are getting the 200mL bottle from Dodson. What I did was screw the cap all the way down and then fill from the bottom and reinstall the shaft, which is sealed with two o-rings, one on the ID and one on the OD of the shaft assembly. I then backed off the cap by 1/2 turn and installed it on the FWD shaft sticking out of the trans. At this point because the cap was backed off 1/2 a turn, there is no real preload on the clutches. You can then just spin the ETS until around several times to make sure the steels and frictions were being soaked by the new fluid prior to adjusting the preload.

View attachment 399631

After the clutches were soaked in the new fluid I tightened the cap all the way down and then backed it off about 60 deg and put it back on the shaft to measure the preload. Make sure the trans is in park so the FWD shaft stays locked and you can then dial in the preload between 18-20Nm. Just keep adjusting the cap tighter or looser until you get he desired preload. I used two different torque wrenches to verify the preload was ~19Nm and they both showed the same results.

View attachment 399632
Punchline, my ETS preload is about half of the 19Nm I originally dialed in.

I officially decided that filling up the ETS from the bottom is a crappy way to service the unit. The argument for using this approach is that as you screw on the o-ring sealed cap, you are creating pressure within the case because of the air being displaced. This is partially true as the outside oring seals instantly, but the oring in the ID of the cap only starts to seal after the cap has been screwed down a ways.

I had concerns with using this method because you are adding the fluid after the case has been assembled, which means after the space between the clutches and steels has been removed due to setting the 18-20Nm preload. The issue is the fluid changes the friction between the clutches and steels so in order to setup the initial preload correctly, the clutches and steels need to have fluid around them.

What I suspect happened is that I setup the preload to 18-20Nm and then added the fluid. As the ETS began to engage, the fluid worked its way in between the steels and frictions and subsequently lowered the preload because it reduced the friction. I ended up pulling the ETS and removing the cap with the custom tool from GreggsCustoms and removing all of the steels and frictions. I measured the clutch stack, which was 35.97mm so it was unaffected and in good order. I then put it all back in the ETS and screwed down the cap, which is where I realized the oring on the ID of the car actually seals much later as you screw down the cap. I then set the preload to 19.5nM and lay it on my workbench on its side so the clutches stay wet. I've been rotating it from time to time to make sure the clutches stay soaked. I'll measure it one last time before I place it back into the case on Tuesday.

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Well…. One would think if you’re gonna charge $50 for a seal, Dodson would be purchasing and using in house the Nissan OEM ones.
 

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Discussion Starter · #73 ·
Well…. One would think if you're gonna charge $50 for a seal, Dodson would be purchasing and using in house the Nissan OEM ones.
Markups in the GTR community are par for the course, but 400% markup on a generic part that fits like crap is lame. The FWD seal leakage issue is not uncommon and I believe early on you couldn't actually buy the seal from Nissan. I suspect Nissan got tired of replacing the whole transmission due to a leaky FWD seal and forced the trans manufacturer to make them available. I didn't take the time to research this and only assumed the OEM seal was not available since an aftermarket seal was offered by Dodson. I had my trans overfilled by 2 quarts for years and never had a single leakage issue with the 12yo OEM seal. When I pulled the trans initially it was leaking from that area, but it was the oring on the ETS connector just above the FWD flange. Anyway, the point of the thread is just to document things so that if others want to rebuild their trans they can hopefully benefit from my experiences.

On a side note, while the trans pan is off I decided to upgrade the two OEM magnets and also add additional magnets to the pan. Not so easy since the pan is aluminum, but I think I found a way to make it work. Magnets arrive Tuesday so I'll post the info with pics once the mod is complete.
 

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For sure… once you have this completed. If you’d like the entire thread cleaned up a bit as to just leave all pertinent posts And to shorten the thread for future reading. Just let me know and I can delete which ever post numbers you provide me.
 

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Discussion Starter · #75 ·
I ordered two different sets of magnets to replace the OEM magnets and 6x extra magnets for additional protection.
  • 1.26" x 0.125" N52 Neodymium Magnets (6x) - $11.99 for a 6-pack on Amazon
  • 1.50" x 1.065" x 0.375" N45 Neodymium Ring Magnet (2x) - $10.94 per magnet on Amazon

The two OEM ring magnets have very little magnetic force so they definitely need to be upgraded. You can get up to 2" diameter magnets in the pan and the ID needs to be larger than 0.700", which is the diameter of the mount in the pan. The pan mount is about 0.365" tall so when you use a 0.375" thick magnet, just put a washer below the washer that holds the magnet to the aluminum pan. When those arrive tomorrow I will post some pics to show what I mean.

The 6x N52 disc magnets were just stuck to the bottom of the pan filter since I really want to capture anything prior to it entering the screen on the pan filter. Remember, I run an aluminum pan so there is not other place to mount them. I'm not sure if these DIYMAG magnets from Amazon are actually N52, but they are very strong magnets and will definitely do the trick assuming no degredation from heat. The seller claims they are used often in engine oil applications and didn't show any degredation, but we'll see.

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Discussion Starter · #76 ·
So the OEM seal arrived and I show the differences below. The OEM seal comes pre lubed for its pleasure and the seal portion that extends towards the driveshaft flange is also lightly coated with grease.

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The OEM seal has a rigid lip that stops the seal once it is pressed to the correct depth, which when you compare the two seals is the depth I originally pressed the Dodson seal. The OEM seal is also smaller on the bottom 1/3 of the seal to help get it started in the case before getting thicker. Surprisingly, the OEM seal is overall taller than the Dodson seal, which means the seal portion that extends towards the driveshaft flange is actually meant to seal against the driveshaft flange as it spins. I can only assume the Dodson seal melted because I did not add lubrication to the back of the driveshaft flange face and because the lip on the Dodson seal is very rigid compared with the OEM seal that is very flexible and angled outwards.

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Discussion Starter · #78 · (Edited)
The new pan magnets arrived today and they are significantly stronger vs the pathetic factory magnets. You don't realize how lame the factory magnets are until you compare them with a more powerful magnet. The new magnets are just slightly thicker than the OEM, but have a much larger ID.

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I had to purchase 1.50" OD x 0.25" ID fender washers to hold them to the pan, but used the magnetic washer that came with the PQY Trans pan as a spacer for the washer.

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Finally, both new magnets installed and secured.

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Discussion Starter · #79 · (Edited)
The trans is back in the car, but I didn't hook everything up just yet. I did the initial fluid fill and will let sit overnight just to make sure there are not leaks before putting everything back together so I can start the car and do the procedure for the second trans fill.

A member gave me a heads up they remember reading that strong magnets have the potential to affect the gear selection sensors, which are located on the upper side of the valve body. This was actually on my mind, but I remember reading that Dodson was putting their smaller neodymium magnets in the dimples on the bottom of the pickup filter, which is where I mounted mine. I couldn't find a picture of this, but read about it on Heritage.

If anyone has information they can provide documenting the potential issues of using strong magnets in the pan, please don't hesitate to provide a link. At this point I'm committed so worst case I'm pulling the pan to remove some magnets.
 

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Discussion Starter · #80 ·
Did the second trans fill and the car is back on the road. Linney recommended that I put ~100 miles on the clutches before putting power to them and I also need to up the line pressure to 21-22bar in the TCM tune. One thing I regret not doing was data logging the stock trans just to understand the line pressures and slippage upon starting the car because these new clutches will require TCM tuning.

The tranny shifts just like it did when it was stock so from that standpoint I don't feel any differences. If I slowly leave from a dead stop the car is very smooth. However, if I give the car ~30% throttle from a dead stop the RPM's flash up as expected, but the clutches grip quickly causing the RPMs to dip and the car bogs. Therefore, I need to tune the line pressure to allow for more slippage until the car gets going because these clutches grip harder than OEM at equivalent line pressures.

I'll need to start reading about the TCM tuning, but in looking at the tables there are likely several ways to attack this problem. I see a specific table called "Target line pressure related B," which is a table that appears to be % of total line pressure as a function of requested torque. I would need to do some logs to verify my interpretation of this table, but potentially I just need to reduce the line pressure in the torque range where I am not getting sufficient clutch slip for starting the car in 1st from a dead stop.

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