Transmission Gearbox Filling advice and Oil Type

[Stag76]

There is a stud partly concealed by the rear mounting that, when you remove it, allows oil and any accumulated swarf to drain from the pump.

The easiest way to fill it is to buy a cheap pump that screws onto the top of an oil container.

TR7 Convertible
Sprint Motor
MegaSquirt EFI

[Hasbeen]

I have a poor mans version of the pump Stag mentions. It is actually a sump drain pump, for sucking the oil out the dip stick hole of boat engines, & putting it into a container. It works just as well at sucking it out of a container & pumping it into the gearbox.

This does the job well, but does require some effort to clean after the job.

What I usually use is an 8" funnel, with 3Ft of 3/8" plastic hose grafted onto it. The funnel sits nicely between the engine & the battery, with the hose in the filler hole in the box. I find this quicker to use & easier to clean.

Hasbeen

[Spike]

Does anybody do anything to flush the old oil through? As I'm planning to go from ATF to Castrol Syntrans I'm a little nervous of any reaction.

Thanks all for your tips and advice which we all help make it a smoother job (pun intended). I did do the job on my old FHC when I was a lot younger and more flexible and it did make quite a difference.

Graham

[Hasbeen]

I did the same thing, ATF to Penrite synchromesh transmission oil about 18 months ago Graham.

I simply gave the thing a 30 kilometer or so run, then a fair while for the last drop to drain out.

I then after filling, removed that pump drain plug Stag mentioned, & ran the engine for about half a minute. The change of oil has had no effect on the gear change, which has always been great, but it may be running a little quieter.

I have never worried about running ATF in the 7s box. If the 8s auto can handle over 300 BHP running on ATF, I've always felt the 7s box should be able to handle a little over 100 BHP running on it.

One thing though, it does put less drips of oil in the drip tray now, so either it's all run out while I wasn't looking, or the oil seals work better with it.

Hasbeen

[TR Tony]

Graham, there should not be any problem with ATF reacting with another gearbox oil - it is still transmission fluid.

When I did the gearbox oil on my TR8 I did find what drained out was pretty filthy ATF of unknown vintage. I refilled (with Motul gear oil), ran it for about 750 miles then drained again & refilled with fresh Motul. The oil from the second drain was also pretty dirty so I guess it helped flush out the rest of the dirty ATF. The process gave a noticeable improvement in gear change quality especially once the box had warmed up, although it is still a little baulky when cold.

I have Castrol Syntrans in the TR7 box, it is very good too, so that's a good choice.

Tony

<font size="1">1981 TR7 FHC Cavalry Blue
1980 TR7V8 DHC Jaguar Regency Red - sadly sold!
1977 TR8 FHC EFI Factory development car Inca Yellow</font id="size1">

[DNK]

I flushed mine with something, can't remember what it was but I got it on one of the chaps website.
Then , As Hasbeen, I used a long tube.
With a lift would be a piece of cake .

Don
Stick a Wedge In It
80 TR7 V8 Kick in the pants

[motomadness1947]

Easy method for filling transmission. Buy some clear tubing of the largest inside diameter that will fit the filler hole in the transmission. get a funnel that will fit into the other end of the 5 to 6 foot long tube. run the tube from the engine compartment (like near the brake master cyls. down to the transmission. tie or tape the tube so the funnel stays upright as you are filling. Pour your choice of oil atf or whatever into the funnel and drink a beer or ale (your choice again while it slowly drains into the transmission. once you are close to specs for trans capacity check under the car where you have nicely placed a few rags to catch the overflow. Once it drips from the filler hole you are done.

[sheetsofsound]

I have been using Penzoil Synchromesh in mine and using the long tube method to fill. I also got some rare earth disc magnets (about 3/4" diameter) and stuck them to the bottom of the trans to hold the swarf. I pull the magnets before I open the drain plug. I don't know how effective it is at keeping the swarf out of circulation, but I sure feel better.

[john rhodes]

Can anyone tell me what is so special about ATF type G oil which it says should be used in my 5 speed box ? Why can't ordinary EP 90 oil be used ?

[busheytrader]

EP90 makes the gear change so stiff you'll grow extra muscles.

ATF was specified by the factory to cure the stiff gearchange that the LT77 gearbox was prone to suffer when cold. It gave a good gearchange but was poor on protection which didn't really matter as the gearbox would be out of warranty when it failed.

You need a synthetic MTF gearbox oil. The search function will bring up a number of brands which escape me, otherwise someone will be along shortly to name them. I used ATF to flush out my gearbox before filling with MTF.

Adam

[FI Spyder]

ATF will work and provide pretty good protection but there are now better solutions. The characteristics of the oil must match the friction requirements of the syncros and vary from one make of transmission to another. The regular EP90 would give a baulky shift into 2nd when cold. We know Pennzoil syncromesh MTF works very well (as well as the GM equivalent). The synthetic Pennzoil Syncromesh not as good (too slippery). These oils are readily available in N/A the rest of world maybe not so much. If you are not from this part of the world, do a search on the subject here to find what others have used in their corner.

[REPLIC8]

I use Castrol Syntrans in my car , used to be called Castrol SMX. Works great, much better than ATF.

[john rhodes]

That's great chaps, thank you very much. Another trip to the motor factors then lol.

[alc59]

Alec Pringle on another forum made the following observation

The late Ken Tomlinson, formerly of the BL works team, knew more about the TR7 and TR8 transmissions than most TR specialists, his knowledge of competition LT77 boxes was possibly unequalled.

After a great deal of testing over decades, his unequivocal recommendation of a few years back was to stick with Motul Gear 300, a product he'd used for quite some years . . . . the standard version for road application, and the LS for competition use.

I got it from Opie Oils

[seven]

.....Can this engine oil be used in the LT77 gearbox? I was told this through conversation. Though I have never heard of this being done, be a bit expensive I would have thought. I checked with the manual and it states SAE 75 EP.
The Rover manual states Type G ATF, which is an automatic fluid. The box is out of an 1986 SD1 so would the auto fluid work ok? Better if it was right about the Mobil 1 0W/40 I have some of that. The box is low on oil so thought I would top it up, but think a change of oil would be more beneficial.
Cheers Peter