TR6 How to change gearbox oil in TR6

[Geo Hahn]

Since I haven't seen any replies I'll offer this: on the TR4 and other cars I have used both methods but fine the funnel and plastic tube much easier.

Get the biggest tube that will fit in the filler hole -- I use 1/2" thin-wall clear vinyl.

 

[Cain]

I did this to my TR6 last fall, but it was when I had the tranny cover off so I could easily access the side hole.

I just got some 80-90W gear oil that came in a tipped dispenser and stuck the tip in the hole and started filling the tranny. When the oil began to drip out of the fill hole, I considered it full. I believe this is the procedure explained in the TR6 Bentley manual. (Note: This procedure is done with the car sitting level.)

Keep in mind that I have a tranny with no overdrive; I don't know if having overdrive would make a difference or not.

 

[Steven]

what's the best procedure for changing the gearbox oil in my TR6? Would it be necessary to use a mityvac hand pump to get the oil in that side hole, or one of those funnels with a long hose?

 

[piman]

Hello Steven,

I use an oil dispenser, basically a big syringe with a plastic pipe end. It holds about a litre of oil. I don't remember what it cost but it is not expensive and makes the job much easier. I use it for gearboxes and differentials.

Alec

 

[Steven]

thanks guys...the reason i asked is because i saw one of those big liter syringe holders with about a 2-3 ft clear vinyl tube on it in Walmart. I thought it would be perfect to access that filler hole on the side of the gearbox. How do you fill it on a level surface when you have it up on jack stands? I can't see any other way to do it, other than put it on jack stands...place the tube in the hole....lower the car to the ground, fill it and look for oil coming out. If you fill it while jacked up, it wouldn't be full...am I right?...or..i could just put in the exact amount that the Bentley manual says under fluid capacities....yeah..that should work.

 

[vagt6]

It's important to maintain proper fluid levels in all the systems of these cars, as indicated by all the literature I've found. Don't overfill or underfill the gearbox, engine oil or differential.

Fill the gearbox until the oil BARELY begins to seep out of the hole in the side of the box. Then, let the car sit for a few minutes or so and check it again. With or without overdrive, that's how you do it.

Messy, but effective.

 

[vagt6]

Sorry, I forgot to include that of course, the car must be on a level surface in order to check the gearbox oil level.

Not on jackstands.

 

[Eric]

I'm not sure how you'd do it if it wasn't on jack stands. Just make sure its level on the stands - which it should be anyway, if you don't want to end up wearing it. (I mean with 4 stands, of course.)

 

[STaylor4]

Filling the transmission can be tricky. First you must remove the 4-sided filler plug. It has pipe threading so it can be VERY tight. If it has become rounded and you can't get a good purchase on it you'll need to get a special tool called "Bolt-Grip" by Irwin. It's a socket that goes over the filler plug and when backed out it tightens down on it. Once that's removed get a new plug at The Roadster Factory, and get a 7/16 8-point socket. I got a set of 5 8-point sockets on eBay for about $12. With that socket you won't round out the new filler plug. Get a hand pump that screws into the top of a bottle of 80W-90 Gear Oil at Walmart and go at it. Level up the car on jacks and fill til it oozes out. Let it sit a few minutes and fill again until it oozes out. Snug down the new filler plug with your new 8-point socket and you're done.

 

[Geo Hahn]

That's weird, I seemed to have responded to the question 6 hours before it was asked -- and now, a dozen years later, it comes around again.

 

[TR3driver]

That's weird, I seemed to have responded to the question 6 hours before it was asked -- and now, a dozen years later, it comes around again.

Neat trick!

FWIW, Sta-Lube markets a gear oil pump that is my favorite for filling the gearbox on the Stags (where the cover doesn't come off and clearance at the side of the gearbox is very tight).
https://www.walmart.com/ip/Sta-Lube...30463&wl11=online&wl12=19866152&wl13=&veh=sem

The pump delivers one ounce per stroke, so you can just count strokes to know how much you put in. Although the pump isn't in the photo, that's what I was using here:


In some cases, the pump body is a bit too big to fit through the hole in the bottle (eg Redline MT-90 comes in a bottle with a smallish hole), but a little quick work with my pocket knife takes care of that

 

[Tom74TR6]

I lifted the carpet on the trans cover and drilled a 1" hole where the filler plug is located. Using a turkey baster and a clear hose, I filled the box from the front foot well. No need to get under the car other than to slide a catch pan under the box to catch the over flow.