My nickel’s worth, I can’t speak for Jag transmissions in general
but my experience with the GM Turbo-Hydramatic 350/400 series is
that these units are well-engineered and reliable, and capable of
withstanding considerable abuse (my son used a TH350 for 2 years
in a racecar at our local track- he had to rebuild the engine
between seasons but the TH350 soldiered on).
The worst condition for any GM transmission to endure is
overheating of the trans. fluid which can be attributed to
negligence of fluid level (I check mine every time I refuel),
failure of the transmission fluid cooling circuit, or in
an extreme case, stopping the vehicle after a long, hard
uphill pull and then shutting down the engine without
giving the transmission fluid time to circulate through
the cooler.
IMO the TH400 is a mighty piece of engineering and
production work, and, though its design is now becoming
a bit dated, can still hold its own againt any other
auto tranny that I’m aware of.
Paul Devoe===================================================
The TH400 is virtually indestructible. I had one in a one ton 4x4 Suburban. The motor I rebuilt, the tranny kept on truckin’. Unfortunately, it does not have an overdrive. OK if you’re gonna stay with the 2:88 rear. If I was putting in a GM tranny, I would up the gear ratio and add a 4 speed auto, perhaps a performance reworked 700R4.
Dennis-----Original Message-----
From: Muggs [SMTP:rdevoe@cln.etc.bc.ca]
Sent: Friday, October 12, 2001 3:48 PM
To: xj-digest@jag-lovers.org
Subject: [xj] GM transmissions
My nickel’s worth, I can’t speak for Jag transmissions in general
but my experience with the GM Turbo-Hydramatic 350/400 series is
that these units are well-engineered and reliable, and capable of
withstanding considerable abuse (my son used a TH350 for 2 years
in a racecar at our local track- he had to rebuild the engine
between seasons but the TH350 soldiered on).
The worst condition for any GM transmission to endure is
overheating of the trans. fluid which can be attributed to
negligence of fluid level (I check mine every time I refuel),
failure of the transmission fluid cooling circuit, or in
an extreme case, stopping the vehicle after a long, hard
uphill pull and then shutting down the engine without
giving the transmission fluid time to circulate through
the cooler.
IMO the TH400 is a mighty piece of engineering and
production work, and, though its design is now becoming
a bit dated, can still hold its own againt any other
auto tranny that I’m aware of.