Engine and Transmission Tech

tips, technology, tools and techniques related to vehicle driveline components

Go to Thread: PreviousNext
Go to: Forum ListMessage ListNew TopicLog In

Jim Blackwood
9406 Gunpowder Rd., Florence, KY 41042
(5599 posts)

10/23/2007 12:59PM

Main British Car:
1971 MGB Blown,Injected,Intercooled Buick 340/AA80E/JagIRS

authors avatar
T5 is easy
Posted by: BlownMGB-V8
Date: February 25, 2017 12:53PM

You could probably say remarkably easy and be right.

So I don't have any photos or links, you can find those by running a search and there is no shortage of youtube videos, some better than others.

Teardown starts with driving out the pin that secures the shifter shaft to the shifter block in the tailshaft extension housing. Nothing fancy there but be sure to capture the pin, spring and ball when you remove the tailshaft. Put them aside together with the block and make sure they can't get lost.

The top cover has two shoulder bolts that are special.

The 5th/rev shifter fork can be removed two ways. Either drive out the pin, or remove the big side pivot bolt from the case. Everything else is standard manual transmission teardown. When you remove the input shaft, besides rotating it so the cutout clears the countershaft, tilt the front of the transmission downwards so the thrust bearing and rollers don't fall out and that will all stay put.

On reassembly reverse the process. There is a neat trick with the caged roller bearings which have a very thin thrust washer. If you install the gear, then drop in the washer, then insert the caged bearing it makes sure the washer is centered. When you put on the top cover make sure the pin hole in the shifter shaft is up and down. It may want to go side-side and then you'll have to take it back apart if you let it. And the most important thing is not to lose track of the pin for the shifter block. If it doesn't come out and you drive another one in on top of it you're well and truly screwed. The only known solution involves destruction and replacement so don't do it.

The videos show putting the block in as the tailshaft is installed and I'm sure that is the easiest way but if you forget, the block can be installed after. It takes some creativity to get the spring and check ball in place but it can be done. I used a small snip of 1/4" plastic air brake line and a dab of grease to position the ball and then fished that out afterwards.

Just wanted to post the highlights. I've been inside some half dozen or more manual transmissions and an equal number of automatics and this was one of the easiest.

Oh, and it turns out that the W/C and non W/C differ primarily in the synchros and the bearings. Synchros for non W/C can be had for about $7 each where non-W/C run $30 and $80 each. Those 3 piece ones are pretty fancy too. And they work well. I'd say if you have to buy more than 1 or 2 of those you might as well buy the rebuild kit. Apparently 2nd gear is the most common one to go. I had to replace 2nd and 3rd so something over $100 for the rebuild as all else was pristine. Not bad these days.


kelly stevenson
Southern Middle Tennessee
(868 posts)

10/25/2007 09:37AM

Main British Car:
2003 Jaguar XK8 Coupe 4.2L DOHC/ VVT / 6sp. AT

authors avatar
Re: T5 is easy
Posted by: kstevusa
Date: February 25, 2017 01:42PM

Thanks Jim for info, Hadn't tried a tranny since old day when I built a Muncie 4sp. The 80 uncaged roller bearings in the cluster was a challenge. The T-5 built as you described, but I let the shifter forks come loose and failed to note their original position. Never got it to shift correctly so purchased a new T-5Z back in 2005. See you all in Lewisburg!

Sorry, only registered users may post in this forum.