Subject: [TR] TR3 rear end

From: Dave MacKay <[email-masked]>
Date: Thu, 7 May 2026 17:33:27 -0400

I used to use that but stopped when I learned that GL4 is what's
recommended. After speaking with Dave Tushingham (former Toronto Triumph
Club president and host of the 'Cheftush' Youtube channel), I drained out
the Redline GL5 and replaced it with Redline GL4.

Over the years I've compiled a list of fluifs to use in my TR3. The notes
that I have for the differential are to use 90W or 75W90 GL-4 EP (Extreme
Pressure) gear oil (e.g., Redline MT90 GL4).

- Cheftush (former Toronto Triumph Club President and host of the YouTube
channel) says it's important to use GL4 in a differential.
- Slightly more than 1 litre required
- Valvoline SynPower 75W90 will eat yellow metal
- Red Line recommends MT90 GL4 for both the TR3A transmission and gearbox.

I used to use GL5 but drained it all and replaced it with Redline GL4.

Regards,

Dave MacKay
1960 TR3A s/n 68639L
near Toronto, Canada

-----Original Message-----

Date: Thu, 7 May 2026 16:17:54 +0000
From: dave northrup <[email-masked]>
To: list Triumph <[email-masked]>
Subject: [TR] TR3 rear end

I happen to have several bottles of this.   Any reason not to use it in
the differential on my 58 TR3a?  It was just rebuilt and i need to fill it
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From: William Smith <[email-masked]>
Date: Thu, 7 May 2026 18:04:34 -0400

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Dave,

I noticed from the picture that this Redline gear oil is GL5.  If your
differential still has brass bits in it, the additives in GL5 may eat them
away.  To be safe, I'd stick with GL4.
GL4 is seldom seen in local parts stores, but can be sourced from the usual
British parts suppliers.

Bill Smith
'72 TR6
'80 TR7

On Thu, May 7, 2026, 4:19=E2=80=AFPM <[email-masked]> wrot=
e:

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<div dir=3D"auto"><div dir=3D"auto">Dave,</div><div dir=3D"auto"><br></div>=
<div dir=3D"auto">I noticed from the picture that this Redline gear oil is =
GL5.=C2=A0 If your differential still has brass bits in it, the additives i=
n GL5 may eat them away.=C2=A0 To be safe, I&#39;d stick with GL4.=C2=A0</d=
iv><div dir=3D"auto">GL4 is seldom seen in local parts stores, but can be s=
ourced from the usual British parts suppliers.=C2=A0</div><div dir=3D"auto"=
><br></div><div dir=3D"auto">Bill Smith</div><div dir=3D"auto">&#39;72 TR6<=
/div><div dir=3D"auto">&#39;80 TR7</div></div><br><div class=3D"gmail_quote=
 gmail_quote_container"><div dir=3D"ltr" class=3D"gmail_attr">On Thu, May 7=
, 2026, 4:19=E2=80=AFPM  &lt;<a href=3D"mailto:[email-masked].=
net">[email-masked]</a>&gt; wrote:<br></div><blockquote cl=
ass=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;p=
adding-left:1ex">Send Triumphs mailing list submissions to<br>
=C2=A0 =C2=A0 =C2=A0 =C2=A0 <a href=3D"mailto:[email-masked]" targ=
et=3D"_blank" rel=3D"noreferrer">[email-masked]</a><br>
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To subscribe or unsubscribe via the World Wide Web, visit<br>
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eam.net/mailman/listinfo/triumphs</a><br>
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<br>
When replying, please edit your Subject line so it is more specific<br>
than &quot;Re: Contents of Triumphs digest...&quot;<br>
Today&#39;s Topics:<br>
<br>
=C2=A0 =C2=A01. TR3 rear end (dave northrup)<br>
<br><br><br>---------- Forwarded message ----------<br>From:=C2=A0dave nort=
hrup &lt;<a href=3D"mailto:[email-masked]" target=3D"_blank" rel=3D"noref=
errer">[email-masked]</a>&gt;<br>To:=C2=A0list Triumph &lt;<a href=3D"mai=
lto:[email-masked]" target=3D"_blank" rel=3D"noreferrer">triumphs@=
autox.team.net</a>&gt;<br>Cc:=C2=A0<br>Bcc:=C2=A0<br>Date:=C2=A0Thu, 7 May =
2026 16:17:54 +0000<br>Subject:=C2=A0[TR] TR3 rear end<br>

<div dir=3D"auto">
I happen to have several bottles of this.=C2=A0 =C2=A0Any reason not to use=
 it in the differential on my 58 TR3a?=C2=A0 It was just rebuilt and i need=
 to fill it
</div>

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From: DAVID MASSEY <[email-masked]>
Date: Fri, 8 May 2026 11:44:29 +0000 (UTC)

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I've used Redline MTL and/or MT90 in my transmissions and diff's for years =
with no issues.=C2=A0 There are other synthetic gear lubs that will serve a=
s well, I'm sure.=C2=A0 Check the label.=C2=A0 If it says it is GL4 compati=
ble you're good to go.
Dave=20

=20

    On Thursday, May 7, 2026 at 11:40:03 PM CDT, Brian Kemp <bk13@earthlink=
.net> wrote:  =20

 Once upon a time I was told not to use GL-5 in a TR6 transmission because =
it ate the brass parts.=C2=A0 I've also seen comments about Redline being g=
ood.=C2=A0 I'd wait for a proper response from somebody that can provide go=
od advice.

Brian=20

-----Original Message-----
From: dave northrup <[email-masked]>
Sent: May 7, 2026 11:58 AM
To: list Triumph <[email-masked]>
Subject: [TR] TR3 rear end

I happen to have several bottles of this. Any reason not to use it in the d=
ifferential on my 58 TR3a? It was just rebuilt and i need to fill it

Archive:=C2=A0 http://www.team.net/archive (http://www.team.net/pipermail/t=
riumphs)

thlink.net

Archive: http://www.team.net/pipermail/triumphs=C2=A0 http://www.team.net/a=
rchive

[email-masked]
 =20
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<html><head></head><body><div class=3D"ydpcb397c34yahoo-style-wrap" style=
=3D"font-family:Arial, Helvetica, sans-serif;font-size:16px;"><div><div dir=
=3D"ltr" data-setdir=3D"false">I've used Redline MTL and/or MT90 in my tran=
smissions and diff's for years with no issues.&nbsp; There are other synthe=
tic gear lubs that will serve as well, I'm sure.&nbsp; Check the label.&nbs=
p; If it says it is GL4 compatible you're good to go.</div><div><br></div><=
div class=3D"ydpcb397c34signature"><div style=3D"color: black; font-style: =
normal; font-size-adjust: none; font-weight: normal; font-stretch: normal; =
font-size: 12pt; line-height: normal; font-family: Arial, Helvetica, sans-s=
erif;"><div style=3D"color: black; font-style: normal; font-size-adjust: no=
ne; font-weight: normal; font-stretch: normal; font-size: 12pt; line-height=
: normal; font-family: Arial, Helvetica, sans-serif;"><div><font size=3D"4"=
>Dave <br></font></div><div><span style=3D"font-size:10.0pt;font-family:san=
s-serif;color:black;"><br></span></div><br></div></div></div></div>
        <div><br></div><div><br></div>
       =20
        </div><div id=3D"ydp39634e4fyahoo_quoted_8556164901" class=3D"ydp39=
634e4fyahoo_quoted"><div class=3D"ydp39634e4fyahoo-style-wrap" style=3D"fon=
t-family:Arial, Helvetica, sans-serif;font-size:16px;">
            <div style=3D"font-family:'Helvetica Neue', Helvetica, Arial, s=
ans-serif;font-size:13px;color:#26282a;">
               =20
                <div class=3D"ydp39634e4fquoted-text-header">
                        On Thursday, May 7, 2026 at 11:40:03 PM CDT, Brian =
Kemp &lt;[email-masked]&gt; wrote:
                    </div>
                </div><div style=3D"font-family:'Helvetica Neue', Helvetica=
, Arial, sans-serif;font-size:13px;color:#26282a;border-left: 1px solid #cc=
c;padding-left: 8px;margin: 0px 0px 0px 8px" class=3D"ydp39634e4finline_rep=
ly_quote_container" data-split-quote-node=3D"true">
                <div><br></div><div><br></div>
                <div><div dir=3D"ltr">Once upon a time I was told not to us=
e GL-5 in a TR6 transmission because it ate the brass parts.&nbsp; I've als=
o seen comments about Redline being good.&nbsp; I'd wait for a proper respo=
nse from somebody that can provide good advice.<br></div><div dir=3D"ltr"><=
br></div><div dir=3D"ltr">Brian <br></div><div dir=3D"ltr"><br></div><div d=
ir=3D"ltr">-----Original Message-----<br></div><div dir=3D"ltr">From: dave =
northrup &lt;<a href=3D"mailto:[email-masked]" rel=3D"nofollow" target=3D=
"_blank">[email-masked]</a>&gt;<br></div><div dir=3D"ltr">Sent: May 7, 20=
26 11:58 AM<br></div><div dir=3D"ltr">To: list Triumph &lt;<a href=3D"mailt=
o:[email-masked]" rel=3D"nofollow" target=3D"_blank">triumphs@auto=
x.team.net</a>&gt;<br></div><div dir=3D"ltr">Subject: [TR] TR3 rear end<br>=
</div><div dir=3D"ltr"><br></div><div dir=3D"ltr">I happen to have several =
bottles of this. Any reason not to use it in the differential on my 58 TR3a=
? It was just rebuilt and i need to fill it<br></div><div dir=3D"ltr"><br><=
/div><div dir=3D"ltr">** <a href=3D"mailto:[email-masked]" rel=3D"=
nofollow" target=3D"_blank">[email-masked]</a> **<br></div><div di=
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From: DAVE HOGYE <[email-masked]>
Date: Fri, 8 May 2026 15:31:41 -0700 (PDT)

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That's fine for a non-standard limited slip.  
 
Dave H. 

> On 05/07/2026 9:17 AM PDT dave northrup <[email-masked]> wrote:
>  
>  
> I happen to have several bottles of this.   Any reason not to use it in the differential on my 58 TR3a?  It was just rebuilt and i need to fill it ** [email-masked] **
> 
> Donate: http://www.team.net/donate.html
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<!doctype html>
<html>
 <head> 
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 </head>
 <body>
  <div style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   <span style="font-family: helvetica; font-size: 12pt;">That's fine for a non-standard limited slip.&nbsp;&nbsp;</span>
  </div> 
  <div class="default-style" style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   &nbsp;
  </div> 
  <div class="default-style" style="font-size: 12pt; font-family: helvetica,arial,sans-serif; color: #333333;">
   <span style="font-family: helvetica; font-size: 12pt;">Dave H.&nbsp;</span>
  </div> 
  <blockquote type="cite"> 
   <div>
    On 05/07/2026 9:17 AM PDT dave northrup &lt;[email-masked]&gt; wrote:
   </div> 
   <div>
    &nbsp;
   </div> 
   <div>
    &nbsp;
   </div> I happen to have several bottles of this.&nbsp; &nbsp;Any reason not to use it in the differential on my 58 TR3a?&nbsp; It was just rebuilt and i need to fill it ** [email-masked] **
   <br>
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