Need Help With 48RE Piston Retainer Galling

rlawless

rlawless

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Mar 20, 2011
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Anyone familiar with this type of galling, or how it could be happening? This is the second Piston Retainer within 5000 miles and a third with less than 100 miles just installed and wearing again.

This began after the transmission was upgraded with an after market HD RV Billet T/C and a shift kit with billet servo and accumulator (which I don’t believe is the cause). The mechanic did completely disassemble and reassemble the transmission only to inspect it (I believe this may be the cause).

I have just completed an entire self rebuild, (all clearance specs are to either the ATSG guide or Red Eagle Power Pak Spec’s) reinstalled the transmission and removed the pan to make some pressure adjustments and once again I have aluminum shavings and aluminum metal flaking in the ATF again with less than 100 miles on it.

I was very meticulous and anal about everything being to spec and I found no evidence of wear or damage to any of the internal hard parts except the ones pictured below.

... ... ... ... ... ... ... Also See photo bucket link below!

48RE Transmission pictures by rlawless1 - Photobucket

The current shavings/flaking are very thin and floatable in the fluid unlike the type of shavings found when the other two retainers went bad which was thicker and accumulated in the pan.

Is this a common problem because of High Horse Power and Torque??

Thanks for any input or idea’s

48RE Transmission pictures by rlawless1 - Photobucket
 
Whats your total end play for the transmission? Is the intermediate shaft spacer there on the shaft and which size did you use? There are 4 different sizes.

I would say that you have a lubrication problem first. The returned fluid enters the piston retainer first. Is your intermediate shaft clear of all debris and the stop (or dam in the recess) and pin in on both ends of the intermediate shaft to retain pressure?

If it is not any of the above issues then you may very well have a problem with clearance. Hard to tell since I am not there but anytime I have seen bad piston retainers its wear on high mileage trannys, heat or lubrication.
 
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raychem said:
Whats your total end play for the transmission? Is the intermediate shaft spacer there on the shaft and which size did you use? There are 4 different sizes.

I would say that you have a lubrication problem first. The returned fluid enters the piston retainer first. Is your intermediate shaft clear of all debris and the stop (or dam in the recess) and pin in on both ends of the intermediate shaft to retain pressure?

If it is not any of the above issues then you may very well have a problem with clearance. Hard to tell since I am not there but anytime I have seen bad piston retainers its wear on high mileage trannys, heat or lubrication.
Click to expand...


I set end play clearance @ .027, I had to use the smallest spacer (.0158?) on the shaft, I manually lined it up by eye closest to center that I could and still have .026 clearance from the Aunulus... I also enlarged the retainer holes by roughly 30%... That was the best I could get it... If the shaft was any lower the retainer would have rubbed on the Anulus... See pic

[ame]http://i1102.photobucket.com/albums/g450/rlawless1/Evolution%20of%20650%20HP%20Dodge%20Ram%20Diesel/48RE%20Transmission/IMG_15752.jpg[/ame]

I have 7 lpm of ATF return flow... All oil holes in the shaft clear and flowing before reassembly and pins in place... Not sure what dam you are referring to?? I was anal about this rebuild to ensure not to have this problem again.
 
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Link to photos of shaft and retainer hole line up:

48RE Transmission pictures by rlawless1 - Photobucket

[ame="http://s1102.photobucket.com/albums/g450/rlawless1/Evolution%20of%20650%20HP%20Dodge%20Ram%20Diesel/48RE%20Transmission/?action=view&current=IMG_15752.jpg"]48RE Transmission :: IMG_15752.jpg picture by rlawless1 - Photobucket[/ame]
 
rlawless said:
I set end play clearance @ .027, I had to use the smallest spacer (.0158?) on the shaft, I manually lined it up by eye closest to center that I could and still have .026 clearance from the Annulus... I also enlarged the retainer holes by roughly 30%... That was the best I could get it... If the shaft was any lower the retainer would have rubbed on the Annulus... See pic



I have 7 lpm of ATF return flow... All oil holes in the shaft clear and flowing before reassembly and pins in place... Not sure what dam you are referring to?? I was anal about this rebuild to ensure not to have this problem again.
Click to expand...

There is a pin on the front of the intermediate, where the trust washer and space ride for the input, at the back of the intermediate, there is what they call a plug with an orifice which restricts flow for OD units lube. That is what I was referring to. I don't modify any orifices since I have never seen a need to so can't help you there.

I will say that the small intermediate spacer may be an issue and you might have to run a .193 or .211 to increase the clearance between the piston retainer and the rear annulus. The intermediate shaft spacer does have an influence there. Also check the OD unit inner race were the one way sprag for the OD unit sits. Check it for wear as a precaution since this is were the intermediate space sits. Run a smaller front pump spacer to compensate for the taller shaft spacer.
 
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My trane was rebuilt by a dodge dealer at 32k and I was there to see the retainer come out, it looked good at that point.
Fast forward about 10k and I did a COMPLETE Rebuild with aftermarket parts and notice my retainer was also wore like yours. I ordered a new one and also drilled a couple small holes in case and retainer and made VERY sure my tolerances were good. I have had ZERO trash other than normal wear in pan after 5 k and 3 fluid changes!
 
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bigblk said:
My trane was rebuilt by a dodge dealer at 32k and I was there to see the retainer come out, it looked good at that point.
Fast forward about 10k and I did a COMPLETE Rebuild with aftermarket parts and notice my retainer was also wore like yours. I ordered a new one and also drilled a couple small holes in case and retainer and made VERY sure my tolerances were good. I have had ZERO trash other than normal wear in pan after 5 k and 3 fluid changes!
Click to expand...

The problem that I have seen at MANY dealers is they don't check clearances! They put in whatever went bad and put it back together again. I am pretty sure only a hand full of dealers keep selectives in stock. I know for a fact that of the 4 dealers around me, I always have to order them.....they don't keep anything in stock. Imagine when they rebuild a tranny from one day to the next.

Remember, truck in truck out asap at the dealer. I know a few techs and warranty is just that, fix it and get it out. They get paid 1/2 or 2/3 of book time so they are not going to be paying attention to small stuff.
 
Did you by chance drill a hole in the return port for rear oiling of the sprang? If so How big is the hole and how far down. I saw someone drill a big hole .125 and kept eatting trans apart.
 
scat said:
Did you by chance drill a hole in the return port for rear oiling of the sprang? If so How big is the hole and how far down. I saw someone drill a big hole .125 and kept eatting trans apart.
Click to expand...

Yes, I drilled the hole to oil the sprag.. It called for a .040 - .045, that is the size I drilled it... All the damage to the retainer was done prior to my rebuilding the transmission and the hole being drilled this last time.
 
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I drilled a .050 and no problem yet! I am going to dis assemble trAns while I wait for motor to be finished so I'll post pics soon
 
Do you still have the inline check valve in the trans cooler lines. How did the one in the transmission look when you had it apart?
 
Yes I took the check ball out, if your asking me about trans condition it was good except for piston retainer :-(
 
I Just finished testing flows & pressures with the "Miller Flow Analyzer" Tool trying 3 different tests..

Between the (outlet) Hot Port and Coolers
Between the Coolers and Return inlet (cold) port
Eliminating the coolers from the Out port to the Inlet Port..

I have good ATF Flow and pressures for every test.

Re-flushed both coolers at least 6-7 times both directions getting a small amount of T/C clutch material...

Left the return line disconnected and directed it into a 5 gal bucket started the truck in neutral while adding ATF back into the pan and could barely keep up with what was pumped out...

The transmission temp sensor is in the hot line line just before the water oil cooler and my temps never leave the 100* mark unless setting idling in gear for along time (20min) I saw it go to 180* put it in neutral and it returned to 120* then drove off and back below 100*... Using a thermo temp sensor the hot line is maybe 65-85* when the gauge reads 100*...

Everyone keeps telling me the damaged piston retainer is from a lack of return ATF flow... Well I call, Bull Sh***T! on that, I have plenty of ATF returning to the piston retainer... Retainer lube holes have been enlarged and lined up with the shaft holes, ensured the shaft holes cleaned out and flowing cleaning fluid... It's got lube!!!

I installed an in line (high flow) hydraulic filter and I'm Gonna let it ride as is for awhile monitoring the pan for damage... After last pan removal (when fluid flow testing) there was barely anything in it.. I will pull the tranny back out depending on material I see in the pan...

Thanks for all of your input..

If your interested here are some Pics
[ame="http://s1102.photobucket.com/albums/g450/rlawless1/Evolution%20of%20650%20HP%20Dodge%20Ram%20Diesel/48RE%20Transmission/"]48RE Transmission pictures by rlawless1 - Photobucket[/ame]
 
My guess is that the new "heavy duty" torque converter is built too tall and it's taking up all the input shaft endplay and forcing everything rearward. Are you running a stock flex plate, or did you go with a thicker billet piece that reduces clearance?

When you install the tranny, is there space between the flex plate and the converter, or is it pretty snug?

Are the splines on the input shaft twisted? If yes, this can also not allow the input to fully seat in the converter and take up endplay.

The gist of all the questions above is basically, if everything checks out fine within the transmission itself, the problem is likely external, especially if the problem started when the converter was changed.
 
Big Blue24 said:
My guess is that the new "heavy duty" torque converter is built too tall and it's taking up all the input shaft endplay and forcing everything rearward. That is what I was thinking... I'm now using Jeff Garmon's triple disc and it is about 3/16" shorter than the T/C I replaced...

Are you running a stock flex plate, or did you go with a thicker billet piece that reduces clearance? I'm using an after market 4mm thick Flex Plate now..

When you install the tranny, is there space between the flex plate and the converter, or is it pretty snug? YES, I have space between the two now... The T/C turned freely after bolting the housing up snug and I had to pull it (the T/C) up to the flex plate guessing about 3/16'' to 1/4"

Are the splines on the input shaft twisted? If yes, this can also not allow the input to fully seat in the converter and take up endplay. No Twist, Using a New Billet Shaft Now..

The gist of all the questions above is basically, if everything checks out fine within the transmission itself, the problem is likely external, especially if the problem started when the converter was changed. I think it was all in the T/C I just replaced...
Click to expand...

The pictures posted above show the damage to the piston retainer before I rebuilt the transmission, which I just completed and installed only 300 miles ago.. After removing the pan to make some pressure adjustments I noticed Aluminium (Very Very thin pieces) floating around at the bottom of the pan and some metal flaking suspended in the ATF, but I think it is from contact between the annulus and retainer... I was pretty close on the tolerances there in order to have the lube holes between the retainer and shaft line up better... From my understanding, forces from all of the extra HP and torque pushes everything in the transmission backwards... I may have to remove the OD unit and replace the selective spacer on the intermediate shaft with a thicker one.. My total endplay was .027 so not a lot of room for movement...

Finally someone that agrees with me about the T/C causing the problem... Everything was fine until the T/C was replaced the first time.

Thanks for your input...
 
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