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TR2/3/3A Rear Axle Vent

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T

TR-3rg

Jedi Hopeful
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Hi,

I drained the oil out of the rear axle last night (1960 TR-3a). I removed the drain plug and it came out slowly and it was gulping. I removed the fill plug while this was happening and it came out fast and steady. I assume the vent in the real axle is plugged or is this typical? Anything to the cleaning the vent? I searched the internet and did not find much on it.


Thanks, Roy
 
It's located on the right side of the center housing, above where the right axle tube enters. You can remove the vent fitting with a box wrench or deep socket and then run a drill bit or some other rod through it. I'd probably not try to clean it in place, as you will shove dirt down and into the differential, and into your fresh oil!

Edit...Forgot to mention, I concur with your thoughts that the vent is likely plugged.
 
Here's what it looks like, and they are always plugged:
P1010301.jpg
 
A little aside...

On the TR3A, I rebuilt the dif and plugged the vent so dirt wouldn't get in while I did the rest of the restoration. I then forgot the plug was there when I installed the dif. The front pinion seal started leaking badly...and THAT keyed me in that the plug was still on the vent! Apparently without the vent the dif will build pressure as it heats up. Leak went right away once I unplugged the vent.
 
On my Tr4, I removed and cleaned the vent some twenty years ago because it was badly plugged with oily dirt, etc.
After reinstallation I slipped a length of clear tubing over the open end and tucked the other end of the tubing back over the rear end of the diff and captured it under the brake line adjacent to the fill plug. It has remained clear ever since....

M.
 

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John,
Nope it a 3.7 ratio (I checked) the car has OD.
That paint dot was buried under an inch of caked on oil and grease when I got the Tr from the first owner in 1981 (maybe he changed the gears??).
When the OD is switched on in fourth we indicate around 2700 rpm at 70 mph.

M.
 
I've been on this site at least a dozen years, replaced the diff gasket at least once, and never knew about that vent until today. Thanks, gents!
 
Merlin63Tr4 said:
John,
Nope it a 3.7 ratio (I checked) the car has OD.
That paint dot was buried under an inch of caked on oil and grease when I got the Tr from the first owner in 1981 (maybe he changed the gears??).
When the OD is switched on in fourth we indicate around 2700 rpm at 70 mph.

M.
Click to expand...

Interesting. I haven't seen the yellow dot before.

Here are a couple pics showing the vent, in case anyone else was wondering where it is...

4256c73e26ae675b7888cedbf1891134.jpg


a4808cd4a53cdfdf85afd6937c888b8b.jpg


The first has tape over the end. The second has the dust cap I mentioned earlier that I forgot to remove later!?!
 
Thanks for the post on the vent. I also never knew it was there. I replaced the pinion seal about a month ago, and it is still leaking a little bit. Now I have something else to check before I replace it again.

Gary
 
Hi,

I popped the vent out and it was plugged. Its basically a 3/8 bolt with a 1/8" hole in it. Nothing to filter out the water or dirt that I can tell. I cleaned it up and slipped a piece of hose on it like Merlin suggested. Its got to be a lot better.

Thanks for the support,

Roy
 
parkerg1 said:
Thanks for the post on the vent. I also never knew it was there. I replaced the pinion seal about a month ago, and it is still leaking a little bit. Now I have something else to check before I replace it again.

Gary
Click to expand...

Hi,

I popped the vent out and it was plugged. Its basically a 3/8 bolt with a 1/8" hole in it. Nothing to filter out the water or dirt that I can tell. I cleaned it up and slipped a piece of hose on it like Merlin suggested. Its got to be a lot better.

Thanks for the support,

Roy
 
Well I checked the vent on my TR3 today, and unfortunately it is not plugged. Guess I will need to try another pinion seal. This time I will put a speedy sleeve on also. My yoke did have a seal mark on it but was not grooved much. I cleaned it up with a piece of sandpaper, but it must not have been enough.

Gary
 
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