Discussion:
low transmission pump pressure

transmission had a bad forward clutch drum, replace drum and reverse drum, seal rings and gaskets. Only have 50psi pump pressure at idle high rpm 200psi. have disassemble transmission and control valve 10 times!and can not see a problem. What am i missing. This is not my 1st transmission to rebuild/ repair.
  • Posted 20 Feb 2013 11:59
  • By TAILLIFT
  • joined 30 Sep'10 - 9 messages
  • Texas, United States
Showing items 1 - 9 of 9 results.
CABLE IS DISCONNECTED
  • Posted 23 Feb 2013 03:29
  • By TAILLIFT
  • joined 30 Sep'10 - 9 messages
  • Texas, United States
How is the inching spool adjusted? I'd completely back off the adjustment & see what the pressures do.
  • Posted 23 Feb 2013 03:06
  • By bbforks
  • joined 1 Mar'12 - 1,437 messages
  • Pennsylvania, United States
bbforks (at) Hotmail (dot) com
Customers love technology- until they have to pay to fix it!
When you replaced the drum did you get a complete assembley?
The thicker metal end band can go in backwards and not allow discs to seat properley. This will give you a low pressure.
  • Posted 22 Feb 2013 08:03
  • By tommytahoe
  • joined 22 Feb'13 - 5 messages
  • Ontario, Canada
think it might just be possible that the new pumps (built-in) relief valve might be defective?
you did install a new pump right?
  • Posted 21 Feb 2013 23:28
  • Modified 21 Feb 2013 23:28 by poster
  • By swoop223
  • joined 23 Mar'12 - 3,691 messages
  • North Carolina, United States
You've been swooped!
swoop223@gmail.com
I know there was a problem with the splines stripping out when they first came out. Did you use OEM parts? Maybe there is some metal stuck in the control valve but you would think it has been flushed out by now.
  • Posted 21 Feb 2013 13:32
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States
The clutches are in good condition. The forward clutch drum striped the slpine. We replaced the forward and reverse drums. We also used a transmission overhaul kit to reassemble. The fluid was never burnt or had a lot of metal. We only have 50psi at idle. The manual said it needs 107psi. At full throttle we get the max pressure 200psi. When the pressure go past 110psi the clutches lock up in forward and reverse. Do we have a valve body problem? We have disassemble it and cleaned a few times and can not find any problem.
  • Posted 21 Feb 2013 13:00
  • By TAILLIFT
  • joined 30 Sep'10 - 9 messages
  • Texas, United States
What happened to the clutches? Was the oil a mess? Could the pump have been worn where it needs more than a gear? How does the transmission react at those pressures?
  • Posted 21 Feb 2013 12:34
  • By mrfixit
  • joined 11 Dec'08 - 1,434 messages
  • New York, United States
strainer is clean and not damaged, the sump filter is also clean. all lines and pick up tube is clear. We have also replaced the pump gear.
  • Posted 21 Feb 2013 10:36
  • By TAILLIFT
  • joined 30 Sep'10 - 9 messages
  • Texas, United States
I have seen other posts about there being a strainer in the control cover. I wonder if yours is clogged? I am not sure about the location.
  • Posted 21 Feb 2013 09:22
  • By rogeriwt
  • joined 10 Apr'07 - 323 messages
  • Massachusetts, United States

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