triumphs
[Top] [All Lists]

Re: TR4 transmission

To: rgs03@health.state.ny.us, triumphs@Autox.Team.Net
Subject: Re: TR4 transmission
From: ArthurK101@aol.com
Date: Mon, 3 Mar 1997 20:59:57 -0500 (EST)
In a message dated 97-03-03 14:52:46 EST, you write:

> Here's the question; can you tell from the serial # what year the trans
>  was from? Serial # is CT 14161. 

Probably.  My opinion is that it is an "early" one.  See below - most trans
#'s were fairly close to the commission #'s.  But my references are rather
vague about transmission numbers.  I do not have my Brit Motor Heritage
documentation with me but my car is so late that it would probably be little
help even if I did.  Let me keep digging on that.

>  I've heard that if it's a later trans I'd need to swap the flywheel,
starter and clutch
>  ass'y. but that an early TR4 trans might plug right in. 

According to Piggott - "the [transmission] unit introduced with the TR4 and
'TCF' 3B's was a development of the previous TR [read TR3] gearbox, differing
principally in having synchromesh on 1st gear.  As a result, the gearbox
casing was 1/2inch longer to accomodate the extra synchro cone.  [caps are
mine ] ALTHOUGH THE TR2/3/3A AND TR3/4 GEARBOXES ARE INTERCHANGEABLE WITH A
LITTLE PERSUASION, the internals of the TR4 unit differed considerably and
were sufficiently strong to cope with the 50% power increase of the
six-cylinder engines." [what this shows is that the TR4 gearbox was used
throughout the TR4A, 250 and early TR6's].  "... the parts catalogues quote
three types of gearbox and clutch housing assemblies for the TR4 [ 1) up to
comm # CT 31636 overdrive 2) from CT 31637 to end of TR4's at CT40304 thru
TR4A CTC50124 and 3) etc.]  the differences are minor, however, and
interchangebility is evidently not affected."  
 
I think yours is an "early" one, that is, one of the transmissions in the
first 31 thousand 636 cars (years '61 thru sometime in early '64.)  That
said, I suggest that you begin comparing your old transmission to the new one
and see what the differences are.  I.e. the differences which would effect
its placement in the vehicle.

Also according to Haynes "The basic layout of the [TR4] gearbox is identical
to the one fitted to earlier models [read TR2/3/3A] but there are differences
which will affect the overhaul procedure [read - no sweat unless you are
re-building the gear box].

>  A little additional info on the OD trans: Pete Fullam said that he
believes that the >  early TR4 trans had the same thickness flange all the
way around the bellhousing >  (as it bolts to the engine) and that later ones
had a thicker flange at the
>  top. This one has the same thickness flange all the way round. It also
>  has the deep bulge for the starter drive and the earlier (flat face)
>  throw out bearing. 

Pete is probably right.  It is logical to assume that the early ones were
more like the TR3 transmissions.  One question here is whether your TR3 is
later than TS50001 which had a change to the starter motor and starter ring
gear.  If it is, you are getting closer to the TR3B and a better fit to the
TR4 gearbox.

>  The shift lever is short like a TR3 but has an aft
>  bend to it. The TR3's is about the same length but is straight. Pete
>  says his '63 TR4 shift lever is longer than this one. Andy Mace thinks it
>  might be an early 4 trans, but suggested I talk to you to be sure.

Sounds like the PO wanted the car to look like a TR3 so he replaced the lever
on the TR4 trans with a TR3 lever.
  
>  If you need any more information please let me know. Any help you can
>  provide is greatly appreciated.

That should do it for now.  If YOU have any more questions or if I have
screwed this up somehow - come back to me!

>  BTW would you mind answering directly rather than to the list? I'm off
>  the Triumphs list temporarily (WAY too much real office work to have time
>  to read it.) No objection to posting the reply to the list, I just
wouldn't
>  get it.

I'll answer to both.  That way you get what I've been able to do and the list
gets a chance to add/detract (Detract? oh, boy - I hope not) to what I have
said.

Cheers and please let us know (you can still SEND to the list) whatever you
do.  

Art Kelly '64 TR4 CT33118L (original owner/ member Vintage Triumph Register)
That was a commercial, ladies and gents - join the VTR)
>  
>  Thanks
>  Rik
>  
>  ***************************************************************
>  Rik Schlierer                "Destiny does not send us heralds.
>  RGS03@HEALTH.STATE.NY.US       She is too wise or too cruel for
>  NYS DEPT OF HEALTH, ALBANY NY  that." Oscar Wilde
>  
>  
>  ----------------------- Headers --------------------------------
>  From rgs03@health.state.ny.us  Mon Mar  3 14:52:41 1997
>  Return-Path: rgs03@health.state.ny.us
>  Received: from gate1.health.state.ny.us (gate.health.state.ny.us [192.135.
> 176.62]) by emin23.mail.aol.com (8.6.12/8.6.12) with SMTP id OAA09996 for <
> arthurk101@aol.com>; Mon, 3 Mar 1997 14:52:39 -0500
>  From: rgs03@health.state.ny.us
>  Received: by gate1.health.state.ny.us id AA25586
>    (InterLock SMTP Gateway 3.0 for arthurk101@aol.com);
>    Mon, 3 Mar 1997 14:52:38 -0500
>  Message-Id: <199703031952.AA25586@gate1.health.state.ny.us>
>  Received: by gate1.health.state.ny.us (Internal Mail Agent-2);
>    Mon, 3 Mar 1997 14:52:38 -


<Prev in Thread] Current Thread [Next in Thread>