Dealership says "loose separator plate bolts" - 4R100

[samiam]

I had an incident with an extremely weak reverse a couple months ago. after that i had problems here and there when in reverse with it seeming "weak", or shaking just slightly. I haven't had problems with the tranny otherwise, except once my mechanic said maybe just maybe there was a slip in the 2/3 shift. Sometimes i think i hear a howl when the TC isn't locked up and i let my foot off the pedal - i'm worried it's the TC or tranny.
I'm still under warranty so i took it to the dealership and they said they dropped the pan and found loose bolts on the separator plate. they are replacing the gaskets in the area of the plate. I think they said there were three bolts total.
they also said the fluid was clean, not burnt, no shavings or indication of any other problem at all. they put electronic "ears" on it for a test drive and didn't hear anything strange from the tranny but maybe the howl is coming from the rear end...
this repair is covered under warranty and extends the warranty for that particular issue for 12 months/12,000 miles.
I asked the dealership how they can be sure this didn't effect the transmission in other ways that will come up after my warranty expires in a few months - they said they found no other indications of any other issues at all.

i'm pleased they found an actual issue, and it sounds legitimate i guess. but what do you smart guys think about it? should i be happy or pushing harder for more analysis? I chose this dealership because local diesel shops recommended it the most as reputable. i had to go to the dealer due to warranty issues. can the separator plate be loose and cause these problems? i don't even know what the heck it does.
how does a rear-end make a low howl sound sometimes when the TC isn't locked?

thanks

[samiam]

anyone? would loose separator plate cause weak reverse?

[FordNutz]

They were talking about the feed bolts under the valve body/separator plate and yes they come loose all the time. The center support will walk inside the case and loosen these bolts causing all kinds of problems from hydraulic leaks. I see it about 75 percent of the time. You say howl in the rear end? Trans or Diff?

[samiam]

Thanks. I found someone on the internet talking about an upgraded center support for the 4r100. have you heard about that? suncoast makes one, i think they said.

the howl is a low noise, not very loud. first i thought it might be the fan up front, but it only does it when the TC isn't locked. when i suddenly let off the pedal i'll hear it as the engine quiets. it tapers off real fast. dealership didn't search it very far since they were only concerned with the tranny, and only the tranny was under warranty.

i also found random posts that maybe u-joint could howl, but i dunno if they would make a noise like i'm hearing. maybe i'll go and check out the fan again.

[samiam]

It seemed like all they had to do was drop the pan to find the problem. Should i be checking these bolts every time i get the trans fluid changed? is it that easy?

Originally Posted by FordNutz

They were talking about the feed bolts under the valve body/separator plate and yes they come loose all the time. The center support will walk inside the case and loosen these bolts causing all kinds of problems from hydraulic leaks. I see it about 75 percent of the time. You say howl in the rear end? Trans or Diff?

[FordNutz]

You shouldn't need to mess with them anymore depending on how they fixed it. If those symptoms come back, then you will know what it is.

[samiam]

Thanks again for the reply. Do you think it's reasonable to say there's no other damage to other areas of the trans due to this issue? Dealer says there's no other indication of wear and tear, no codes, no performance issues. And according to my gauges the trans didn't overheat, it was cool.

[FordNutz]

I can't say but there shouldn't be. It looks like it tested out OK.

[samiam]

Got my truck back. Seems to drive fine. I had put the XLE4 PCM back in it (original equipment) for the trip to the dealership. I gotta get the PMT1 and the DP Tuner back in there.

[samiam]

I gotta say it feels like the truck is really back on its feet now. like it's smoother and tighter driving down the road. could all that just be in my head or could the separator plate repair make that much of a difference? i guess it could have been loose for a long time and now i feel some subtle differences.