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Discussion Starter #1
Hi all, looking for some help to see if Im in trouble after a rebuild.

Long story short, put in a new motor and rebuilt 4r70w with extra direct and forward clutches, sonnax forward drum, 300m direct drum. All clutch pack clearance was in spec, final clearance in spec as well.

Drove the car 10 miles, everything shifted ok and seemed to run good. Had to pull the motor and trans due to thrust bearing issue in the motor.

I decided to drain the fluid and drop the pan while it was out and saw more sludge than I was expecting. Fluid was also shimmery, no big particles. All the sludge smears to a paste. Is this much normal for a new trans? Clutches breaking in or something gone wrong??
38743
 

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A fresh rebuild shouldn't have chunks of stuff in it.
 

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Discussion Starter #3
Thanks for replying @Grog6. The picture is a bit misleading with regards to that, if I touch any of those black splotches they are like fine dust trapped in fluid rather than chunks.

Its like the dust that accumulates on the magnet but I've never opened up a pan after fresh rebuild to see how much is in there after such short miles to say what's normal.
 

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Was the convertor filled with fluid before install, and in correct position once in? Looks like too much to me. I've never seen it stick together like that and I've seen a few bad trans.
 

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Discussion Starter #5
Hi Zep - yea there was 1.5 qt put in the converter and about 1/8" play between flexplate and and mounting pads before bolting up. It was seated in the pump correctly.

38744
I smeared out those clumps with my finger for another picture, im not sure why it clumped like that other than possibly the trans has been sitting for a month while i checked out the motor. It looks a bit better but still a decent amount around the magnet. The chunks around the plug are spatter from getting the plug in.
 

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Sounds like convertor was good. I'm not an expert by any stretch, but seems like a lot of material. I guess the real question is do you want to dig deeper while it's easy to get to or put new fluid in and send it?

One thing I will say, is if the trans took a crap on you before this build there could have been a bunch of crap in the lines and cooler. Make sure to blow those out completely.
 

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Discussion Starter #7
Yea thats the crossroads im at now. I never had an issue with this trans pushing 500hp behind a stock bottom turbo 302.

All the trouble started with the new motor. Dropped it in with the trans as it was unbolted from the 302 and thrust bearing failure within 30 miles. I was certain the converter clearance caused it, as I didnt bother to check it, by my mistake, and after measuring things out it only had .010 clearance. Had it pulled, crank cleaned up by a shop, and reassembled.

This time decided to rebuild the trans while it was all out. It all came apart with suprisingly good looking clutches with some hotspots on the steels to be expected with the abuse it took, for a stock 4r70w with jmod and Precision converter.

So all went in together reassembled again, and thrust bearing failure again. After disassembly again, it appears there was a nick on the thrust surface left by the cleaning that I missed that left a line in the bearing and i think the continual gouging continued to eat the bearing. I put too much faith in the machine shop and didn't look at it close enough, but it was hard to notice. Anyways thats the only smoking gun I can find as all clearances in the bellhousing seem fine, trans line and cooler line pressure checked out good.

So here I am again had the thrust face polished, bearing modified per clevites reccomendation for better oiling, and going thru everything transmission related to try and make sure it doesnt happen again. The amount of material does bother me but for the short time driving it I didnt notice and issues with slipping or shifting.

Quite honestly haven't had the best of luck with this new motor and this is my last stab at it. End Venting.
 

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I had a 200R4 GM trans attempting to hold 532lb/ft and finally found it we didn't have enough pump. Spent a load of cash on the new pump and solved the burning of the trans but never liked the way it shifted.

Pressure gauge on the trans at all? I'd be to the point of taking it to a shop. I'm not knowledgeable enough over you get past throwing it in there. Interesting that it doesn't seem to slip but has that much material. Maybe it's the extra clutches?
 

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Discussion Starter #9
Yea the kicker is that I haven't put much throttle behind this transmission as it was a moderate 10 mile ride to make sure the motor was behaving appropriately.

Maybe it is the extra clutches dragging. All of the clutch packs air tested ok going together. Transmission line pressure test was OK, although maybe slightly higher than expected on part throttle in drive at 225 PSI. Cooler line pressure was about 45psi tops under throttle. Only reason i was verifying this stuff is because it has impact on the force applied to the crank thrust bearing.

Im going to open it up and take a look for anything out of the ordinary and air test again and verify EPC is working as expected. It only makes sense while its out - the trans itself has never given me a problem.
 

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Good luck! Sounds like the wise thing to do, since you know what changed. Look there first.
 

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A 500hp 5.0 block; that sounds like fun waiting to happen. :)
 

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@Zep5.0 appreciate it will report back here with findings as I hate inconclusive threads.

@Grog6 I must have had great luck or did something right as its lasted me 10 years albeit not a daily driver but lots of thrashing and 10-11sec passes.

Ironically this new motor with dart block and forged internals was to ease those concerns but so far has been nothing but a problem for me so far
 

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I have to admit, the guys I see with zippered blocks are usually on Nitrous.

The "Hell, give it another 50" crowd. :)

Turbos are much gentler, lol.

500 seems to be a sweet spot, but there's a limit there somewhere; I've seen a bunch of mustangs hit it with nitrous.

But those stories are more like, "well, we cranked the boost up another 10psi, ran the same 100 shot; all our meth and ice injection is gone, but we went for it anyway..."

:)

That's a damn nice spot, too, so I see why it's popular. :)
 
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