TR4/4A TR4 Tranny -did it come non synchro??

[Adrio]

I have just installed my spare tranny in my TR4A (see other thread). I notice that this one appears not to have synchro in first gear. Does anyone know if they ever made a TR3/TR4 non first synchro gear box BUT that did have the long bulb for the TR4 type starter. My guess is this is what I have, of the 1st gear synchro is shot while the others are fine.

The previous gear box I had in that car was a TR6 gear box and this "new" one acts much differently then it when I try to go into 1st gear. In fact it acts just like my TR3 gear box.

Any clues to this would be nice. I had thought about merging my spare TR3 O/D box to this box, but after consulting this forum I realized it was too much work to bother. This new question throws that door open a crack only.

 

[Geo Hahn]

[ QUOTE ]
...Does anyone know if they ever made a TR3/TR4 non first synchro gear box BUT that did have the long bulb for the TR4 type starter...

[/ QUOTE ]

Sounds like you have a post-TS50000 TR3A gearbox. What you call a 'TR4 type starter' was actually introduced with TS50001 in mid-April, 1959.

 

[martx-5]

That's what he's got. They started putting in the first gear synchro boxes in the TR-3B's.

 

[Alan_Myers]

Hi Adrio,

You *either* have a TR3A or earlier gearbox that was installed in a later car and mistakenly identified as TR4A *or* a TR4/4A/3"B" gearbox with the first gear synchro that's gone out (I've got one of those in the garage!)

All TR4/4A/3"B" came with full syncrho boxes.

It's easy to tell TR3A and earlier from the later gearboxes.

The TR3A and earlier has large oval boss cast into the LH wall of the g'box. On one edge of this boss you should find a serial number stamped, starting with "TS" prefix.

If it's a T4/4A/3"B" g'box, there will be no oval boss on the wall of the gearbox. It will just be a smooth, curved wall. And the serial number is instead stamped on the LH boss for the clutch release shaft, usually on the flat rear-facing side, starting with "CT" prefix.

Look at Moss catalog illustration https://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=29131 This is a TR2-3A g'box, as can be seen by the oval boss on the side wall (just above part #66, drain plug)

You noted the different bellhouising shape to accomodate the change in starter motor, distinguishing pre-TS50000 from later g'boxes. Also, the pre-TS50000 g'box top covers were fitted with a dip stick to check oil level in the box. The top cover was a different casting, with a boss for the dipstick.

Much later gearboxes used on the 6-cylinder TRs and in the saloon cars have a thicker bell-housing mounting flange and have a variety of other serial number prefix codes like "MB" and "MG".

NOTE: If at any time a gearbox was *factory* rebuilt and sold through the exhange program, the serial number should have a different letter prefix or suffix added.

Many of the internals of the 3-synchro and 4-synchro gearboxes are *not* interchangeable. Gearsets, mainshafts and many other things are different.

Cheers!

Alan Myers
San Jose, Calif.

 

[Alan_Myers]

Hi again,

I just noticed on eBay that there are two TR3A or earlier, 3-synchro (non-synchro 1st gear) boxes being offered . The photos are useful by clearly showing the large ovals on *both* sides, part of the early g'box casting.

Plus you can see the boss for the dip stick in the top cover, RH side. I can't be certain from the photos if these are drilled for dipstick, though. At some point the dipstick was discontinued, but top covers still had the boss cast into them, but just weren't drilled out. The dipstick boss was completely eliminated from the design of the top cover of the 4-synchro g'box.

Finally, note the short/straight shifter levers on both. These indicate TR3A or earlier. But, because they are very easily interchanged with the later, longer, curved shifter of the TR4/4A, use this identification clue with caution.

4567172070 is a pre-TS50000 box with the short starter bump in the bellhousing.

4567172464 might be a post-TS50000 g'box with the longer/deeper starter bump in the bellhousing, but it's hard to tell due to the small photo and scruffy paint on the gearbox.

Both these are definitely *not* TR4 gearboxes (no matter what the eBay seller says). Mainly I reference them to show the tell-tale ovals in the casting on either side. On most TR3/3A gearboxes, the "TS" prefix serial number is stamped in one or the other... I think the RH side (correcting my previous response).

A TR4/4A/3"B" box has smoothly curving outside walls, no oval in the casting, and the "CT" prefix serial number on the LH side, stamped on the rear-facing side of the boss that the clutch shaft passes through.

Alan Myers
San Jose, Calif.
'62 TR4 CT17692L

 

[Adrio]

Alan,

Thanks for those two replies. I think I have a TR3 box with a TR4 shift lever. Here is what I have, perhaps you can confirm.

The replacement box had the large oval boss on the left with the "drain" plug which I assume is the level indication as well. Also this box has the longer bulge for the newer starter.

I guess my confusion is in the bulge for the starter. I never knew that the TR3 came with the newer starter and hence that there are TR3 boxes with the longer bulge.

Both boxes have a number on the right hand side. The first box has 306812SM and the second one has 302551. These numbers appear to be cast in to the aluminium so I don't know if they are serial numbers or not. And from where you describe the serial numbers to be I am looking in the wrong place. When I get home I will look again.

Does all this mean I may have a (late) TR3 type gear box now (but with the larger bulge for the newer starter)? If this is the case are the guts the same as those guts of my spare TR3 gear box that has overdrive? you can see both my spare O/D box and my current non-O/D box (that is in the TR4 now) at my page with boxes . Look at TR4/TR4A transmission no O/D picture for the one that is in the car now (and that I am not sure what it is) and look at TR3 trransmission with O/D picture for my spare TR3 with overdrive. Would those two pictured boxes have the same guts (they both have the boss on the left)

If only all this had happened just before winter I would have had 6 months to play with it and not feel like I was taking away driving time.

 

[Alan_Myers]

Hi Adrio,

Whoops... I may be confusing more than clarifying, and I am wrong about one point above. I just looked at the TR4 gearbox in my garage and noticed it does still have the dip stick boss, undrilled and unused, in the top cover. D'oh!

Looking at your photo of the TR gearbox w/A-type OD:
-The oval castings on the sides mean no later than TR3A.
-The dipstick means TR3, probably fairly early.
-The serial number is usually stamped on the edge of the RH oval. The cast in numbers you noted are parts numbers, not the serial number. Keep looking.

I think you will find the serial number is under TS50000, since the starter bump is the short, early type. Also, there is only one OD switch on top, enabling OD action on 3rd and 4th gears. Later 4-cylinder cars had two switches, enabling OD on 2nd, 3rd & 4th gears (Some 6 cyl. cars went back to the single switch arrangement). I'm not sure when the transistion from 3r/4th to 2nd/3rd/4th OD capability occured. Maybe someone else can tell us.

The gearbox you have identified as TR4/4A without OD also looks to me like TR3, but later, after TS50000. It has the elongated starter bump to accomodate the later starters.

I suspect both your gearboxes shown are 3-synchro versions, one fairly early (pre-TS50000), the other a little later (post-TS50000). Your best means of confirming that would be to locate the serial numbers. These two gearboxes probably *are* largely interchangeable internally, except for the special mainshaft for OD. Neither of these will be very interchangeable with later TR3"B"/TR4/TR4A gearboxes.

There were four different shift levers used on TR gearboxes. Earliest was a two-piece type, TR2/3. Then there was a TR3/3A type, shor tand straight I think. Next came a TR3B/4 type, which is what's fitted to both your gearboxes. Finally there is also a TR4A type. I don't know all the distinctions, but definitely recognize the ones on your both your gearboxes as TR4.

I'm attaching a photo of a 1962 TR4 4-synchro gearbox (non-OD), for comparison. Note the lack of oval castings on the sides. Also, the location of the serial number is pointed out, but won't be in the same location on your gearboxes.

Alan Myers
San Jose, Calif.
'62 TR4 CT17602L

 

[Adrio]

Thanks Alan.

I am fairly sure that I have a late TR3 gear box now. This is a plus and a minus. I don't have first gear synchro (minus) but I have a glimmer of hope that I can turn it into an overdrive box using what I have at hand (plus). I think if I had to pick between overdrive and synchro I would pick synchro. If I can't find a way to trad the two working boxes I have (and even throw in the defective one) for a working TR4 overdrive box between now and winter, then I think I will pull the box from my TR4 and try to see if over the winter I can make me a late TR3 overdrive box that will fit in my TR4 in time for next summer driving season.

Thanks again for all the help. I will take a piece of paper and see if I can make a rubbing of the serial numbers and post them here to give the final word on what I have.

This is a fun and infomative thread. I am enjoying it, as it has turned a "problem" of a failed tranny into a learning eoportunity. I thank you all for it.

 

[TRTEL]

Hi Adrio,
I really can't add to the knowledge base here, but do have a bit of trivia to add. Went to a VTR national in Boulder, CO (1990 perhaps?)and they had flown in Ken Richardson the development engineer for the TR2 and the competition dept. in the fifties, as the guest speaker. As luck would have it I'd just come back from the autocross and people were cleaning up their cars for the show and he was wandering by looking at the cars. So I immediately assaulted him with questions for the next 15 minutes. One of which was what was the story behind the TR2 and early 3 serial # plates which mention a patent for a SYNCHRONIZED first speed. Turns out that the design was completed and they had built a few boxes, but when it came time to put it into production the beancounters told them to use the existing, post war crash first gears that were available on the shelf in large quantity. And I suppose was a cheaper gearset to produce. So they didn't change until buyers began to complain. Anyway that's my story and I'm sticking to it.
Tom Lains

 

[Adrio]

Tom, thanks for the factoid.

Alan, I could not resist finding out so on the way to bed I hit the garage and grabbed all three serial numbers. Unfortunately only the on on the dead tranny looks anything like a number you mentioned.

Here is what I have.

1) The dead tranny was # CT67395 and looks like the TR4A tranny you posted a picture of only the output piece was round and not square as your picture (my guess is this is a TR6 tranny). It has the long starter bulge and was all synchro before death.

2) The tranny now in the car has # 10G-59 (or it could have been LOG-59 as the first two characters could have been letters of numbers but my guess is numbers). It looks like a TR3 tranny except it has the long starter bulge. It does not seem to have synchro in first gear. This is one of the ones shown on my web site from my previous post.

3) the spare overdrive tranny has # 6C 59-/ (spaces and dash and slash are intentional). It has the short starter bulge and cam in my TR3 parts car which turned out to have a TR2 head on the engine but a TR3A serial number so who knows what it has in it. This is the other one of the ones shown on my web site from my previous post. It did not have first gear synchro when I drove it.

So it is still not 100% solved but darn close. Either way the tranny tunnel goes back on tomorrow and firther "work" is put off until winter or until I am looking for something to do (which has not happened in 25 years!) whichever comes first.

 

[Alan_Myers]

[ QUOTE ]
I think if I had to pick between overdrive and synchro I would pick synchro.

[/ QUOTE ]

Hi Adrio,

Personally, I'd probably choose the opposite, OD over 1st gear synchro. That's partly because the first gear synchro was pretty much gone on my TR4 for the last few years I had the car on the street and I never really missed it. Maybe I'd feel differently now, but I just didn't often find the need to downshift into 1st gear while rolling. On the other hand, highway rpms were always pretty high even with a 3.7:1 diff (14" wheels and low profile tires) and an OD would have been a big relief.

I don't have a good photo of the OD gearbox now in my TR4... Heck, it would just confuse matters more, anyway, since it's a Stag or 2000 gearbox with a few subtle external differences from the TR4/4A g'box (AFAIK, the guts are TR4A, though).

It will all work out, I'm sure. If I happen to see a TR4 OD gearbox lying around somewhere, I'll let you know! (On second thought, I'm gonna need one eventually... for the next project. ;-)

Cheers!

Alan Myers
San Jose, Calif.
'62 TR4 CT17602L

 

[Adrio]

Alan, I mistyped my last. I meant to say I would pick O/D over Synchro. I would rather have the lower RPM then the first gear synchro. I must be tired and should have gone to bed, but I could not resist this one.

Do those serial numbers mean anything to you?

I am sure I can build an O/D unit from what I have. I am even thinking I should bite the bullet and go for it now while the car is part way apart. I have no idea how long it would take, but if I did it would make it easier to decide. I just don't want to spend the rest of the summer with no TR4 since I have only driven it 750 miles since the restoration.

On secnd thought I have a "book" by Standard-Triumph motor comp[any, inc called "schedule of Repair Operation times" and it claims to remove gear box as a unit and refit with engine in position + remove O/D as a unit and refit + dismantle box completely and fit any new parts = 14 hours. So I guess I have an idea how long it would have taken a mechanic who worked on these cars every day to do what I want to do.

 

[Geo Hahn]

[ QUOTE ]
...I think if I had to pick between overdrive and synchro I would pick synchro...

[/ QUOTE ]

Wow, even with my only occasional high speed driving I would much prefer the OD. I truly never miss the 1st gear synchro on the TR3. Just never have a big need to downshift into 1st except when rolling up to a stop sign and then you can do it before the car stops if you can catch the moment.

After so many years with the TR3 of shifting down into 2nd just long enough to stop the input shaft motion before shifting into 1st I even do that on the TR4. Come to think of it, I even do that on my wife's Toyota.

Oops, sorry... didn't see your correction. Was ready to trade my synchro '4 gearbox to the first OD owner who spoke up and wanted to get rid of that pesky overdrive.

 

[Alan_Myers]

Adrio,

1. The broken TR4ish tranny sounds to be truly TR4A. Do you mean the driveshaft flange at the rear is round? I've not seen a round one, but it's possible it's been swapped from a later car, I'm not all that familiar with the 6-cylinder cars. As far as I know, the driveshaft flanges would be relatively interchangeable amoung all the gearboxes TR2 through TR6.

2. and 3. I'm sorry but those numbers mean nothing to me. You should find "TS" followed by 3 or 4 or 5 numbers. Another possibility is that those gearboxes came out of something other than a TR. Triumph used similar gearboxes in other cars, usually easily identified by a different two letter prefixed serial number. (For example, my car's current gearbox has "MB", indicating that at least the external case is from a Triumph 2000 sedan. The internals are supposed to be TR4A/overdrive specification.) There is one other possibility, which might have occured if either or both gearboxes were ever rebuilt under the factory exchange program. In that case, another letter was usually added, either before or after the serial number.

2. Yep. Pretty sure it's that's a later TR3A box, post-TS50000.

3. This one sounds like pre-TS50001 gearbox, especially since it has a dipstick *and* the short bulge for the early starter.

2. and 3. Good news is those two boxes *might* be pretty compatible with each other. According to Moss' catalog, there was a change in input and main shafts at gearboxes TS26824/TS26825 (early 1958), including the input shaft bearing assembly. But, all other internal parts appear to be interchangeable across the line of non-synchro 1st gear boxes. Further, if *both* of your gearboxes are later than TS26824, they are even more likely interchangeable.

See why it's important to verify the serial numbers? Try wire brushing or using steel wool to clean up the serial number area. If TR gearboxes, they will have a TS prefix followed by 1 to 5 numbers. Look all the way around both oval castings, but Moss' catalog shows it on the top edge of RH one.

Since you are considering having work done, I'll pass this along. Just last week I got an email from John Esposito at Quantum Mechanics, regarding an A-type OD rebuild. Here's an excerpt from his email: "The price to rebuild an overdrive unit (A or J type) is 5 hours labor at $65/hour. Parts can vary significantly. If it just needs the o-rings, seals and gaskets, that is about $25. However, if it needs a clutch, that is $225, the new accumulator assembly is $175. Unfortunately I can't tell what it needs until I get it apart. Rebuilds are warrantied one year and all units are bench tested before shipping."

I'm sure similar time and materials would be involved in a gearbox rebuild, but I don't have any details.

If rebuilding the overdrive, it's highly recommended to rebuild the gearbox at the same time. Since the two units share oil, one or the other that is in less than ideal condition can contaminate and damage the other.

The A-type on your TR3 gearbox *should* be the early A-type. It's the same type I've got on my TR4. That one is more desirable to racers because it uses the larger accumlator piston and shifts into overdrive faster and crisper than the later version of A-type or the J-types. The later ones were increasingly detuned to make them more "comfortable" for customers (but there are a few tricks that can be done to make them snappier).

I'd strongly suggest keeping that A-type, no matter what. It can be used on TR2 through TR6. If you decide you want full synchromesh, all you would need to do is get a TR4 gearbox and have it rebuilt to be compatible with overdrive. Non-OD gearboxes are pretty cheap. All the necessary parts for OD conversion are available from Quantum Mechanics and elsewhere.

You might want to get in touch with John. His website is www.quantumechanics.com He rebuilds both the gearboxes and the overdrives, has seen quite a few and can probably tell you a lot more about them than me!

Geo,

Sounds like we all agree, OD is a more useful than 1st gear synchro. Heck, today most people don't even seem to know how to shift a manual transmission, let alone deal with a non-synchro 1st gear! We're all giving away our ages!

Tom,

That is a very interesting tidbit! I wasn't aware TR3 had that patent info on the commission plate. Just think, if that were done to in today's litigious world, there would no doubt be a class action lawsuit against Triumph for failing to deliver as labelled, false advertising and all that.

One thing to remember is that the company's name was "Standard Triumph", which earlier was the "Standard Car Company". They chose that name because, supposedly, their cars were built with "off the shelf, standard parts", making minimal use of expensive, specially tooled items. So, it's not surprising to me that they'd have a stockpile of gearboxes and insist on using up existing supply before going to an already available upgrade. I bet that happened alot!

Oh, and Adrio, the last time I drove my TR4 was 1986. /ubbthreads/images/graemlins/nopity.gif I'm hoping it won't be too much longer, though! /ubbthreads/images/graemlins/driving.gif If I can just get over this severe case of shipwright's disease! /ubbthreads/images/graemlins/hammer.gif

Cheers!

Alan Myers
San Jose, Calif.
'62 TR4 CT17602L

 

[Adrio]

[ QUOTE ]

Try wire brushing or using steel wool to clean up the serial number area. If TR gearboxes, they will have a TS prefix followed by 1 to 5 numbers. Look all the way around both oval castings, but Moss' catalog shows it on the top edge of RH one.

[/ QUOTE ]

I will take one more stab at finding a proper serial number tonight after work. I must admit I was tired and it was late last night when I looked. Though I did use solvent and cleaned the area well, but I am the first to admit that midnight is not the best time to be looking for somthing I have never seen.
[ QUOTE ]

Oh, and Adrio, the last time I drove my TR4 was 1986.

[/ QUOTE ]
Wow. 1986 to now. People had better stop razing me about taking five years per car! I am sure your final product will be worth it.

 

[Andrew Mace]

[ QUOTE ]
...One thing to remember is that the company's name was "Standard Triumph", which earlier was the "Standard Car Company". They chose that name because, supposedly, their cars were built with "off the shelf, standard parts", making minimal use of expensive, specially tooled items....

[/ QUOTE ]

Well, yes and no. The quote often attributed to Standard's founder, Reginald Maudslay, goes like this: "I want my car to be composed purely of those components whose principles have been tried and tested and accepted as reliable standards, in fact, I will name my car the Standard car."

Remember, this was back in 1903, when Cadillac was becoming "The Standard of the World"; the term Standard at that time referred to something to aspire to, or a very high level of quality or acheivement. Of course, the nameplate was pretty much gone by the early 1960s (except in India) because the connotation of the word Standard had become "mundane" or "ordinary."