Diff removal from GT6 Mk3

[LMC]

Hi there

 

Been a while since I've posted anything in here, so the GT failed its MOT months ago and I need to remove the diff to get it looked at, probably by Mike Papworth, unless theres any one in the Berkshire area who could be recommended.

 

Anyhow before that can take place I need to acuatally get the diff out. The car is up on stands, but before I start pulling this off the car I wanted to see if anyone had any tips of tricks to removing the diff and are there any jobs that need to be done whilst it is out?

 

Cheers

 

Laurie

[LMC]

oooops, placed this in the wrong section of the forum.....sigh

[clive]

Rotoflex or non-rotoflex?

 

If non rotoflex, Exhaust off, undo the shafts from the diff, and the prop. They can be left in situ. 

Undo the spring studs from the top of the diff (cover plate inside the car)

Trolley jack under the diff, undo the front mounts, then the rears (not so easy!) and lower the diff, it has to angle pointing down at the front.

 

Rotoflex, I suspect you need a spring lifter, undo the spring eye bolts, and possibly the lower wishbone (easiest from the chassis bracket) otherwise the same. I think.

[LMC]

It's a rotoflex, and luckily I got a spring lifter for Christmas a couple of years ago.

[Steve C]

Not the easiest of jobs! I swapped mine last year, and even with the less cramped mechanicals on a Herald, it can be a s*d of a job. If you can access/rent a garage lift and a trans jack it will be a lot easier. The biggest problem is having the diff perched on a trolley jack and trying to get the bolts aligned through the rear mounting lugs, while lying on your back in a confined space and being unable to bring any real strength to bear other than from your shoulders. A certain amount of immoral brute force and some levering bars help.

 

Regards

 

Steve C

[Pete Lewis]

last one i did was in 1967 on my rather rotten and rusty 59  948 shot the diff taking off in a hurry ( yes in a 948) , so in dads  garage 50yds from the house with a long lead and dim lead lamp and 6" of snow i proceeded to undo everything , the spring whacked up against the floor and the long  tail bolt was a sod to  remove in the dark

and all I needed was a simple output shaft that could have been changed in situ

    well we all learn as we go through life ,

     as my old tutor said  Lad you will find many guys out they some have 1 years experience 40 times and some have 40 years experience Once !!

 

               very true .....just trying to work out where i fit in ...or not  

 

sorry doesnt help with the removal....but the suns come out 

 

Pete

[clive]

Non roto on a swing spring, about 2 hours on the driveway....last did it in 2008, the morning of teh RBRR as the diff fitted was leaking, and I woke up early doing the maths and realised it wouldn't make 2000 miles without going dry.... All fitted by 9.30am!

 

Roto is tirckier, the rotoflexes are very springy!

 

While in there check the lower trunnion bolt, it it is free worth taking out and clean/lubricate. 

[trigolf]

I have a Mk2 Vitesse ( Rotoflex) and previously have removed/replaced the diff using a spring lifter several times in the past, but decided to try another way last time I did the job, as described below. It may sound complex, but is easier than it sounds and saves a lot of time. However, please do not attempt this method if you are in any doubt about your abilities.

 

Slightly loosen,the rear wheel nuts. Jack up the car under the diff and support on axle stands under the vertical links.Then remove the rear wheels. It's very important to position the axle stands directly under the wishbone's outer trunnion bolt 'tube' in the middle of the wishbone.  Lower the car very carefully onto the stands, checking the final resting position of the wishbones on the stands ( As the spring takes the weight,it will tend to flatten out slightly, so constantly check the stands position until the cars' full weight is safely supported. Check and check again that the car is properly and firmly supported. 

Remove the spring fixing access plate. Find a couple of bits of wood, about 2" x 2" x 3"  ( from memory) Then position these on top of the spring, directly next to the the outer edges of the spring clamp plate. You should be able to 'fiddle' these blocks into position either through the spring clamp access hole and/or reaching into the tunnel.  The idea is that the wood blocks should be a snug fit between the top leaf of the spring and the underside of the spring tunnel - to stop it moving up when you remove the spring clamp plate/nuts. Ensure that the blocks are firmly wedged in position. Then position the trolley jack under the diff to just take the weight, but no more, Do not allow it to jack the car off the axle stands. You can now remove the bolts/nuts from the halfshafts and rear propshaft flange. I found that I did not need to remove the exhaust pipe,but you might have to on a GT6. 

Now you can gradually loosen and remove the spring clamp nuts and clamp plate. Then using the double nut locking technique unscrew the studs from the top of the diff. You can cover the stud holes with masking tape to stop dirt ingress into the diff. Then remove the diff mounting front and rear nuts/bolts.The diff is now ready to come out, by gently lowering the trolley jack. As I was doing the job on my own I also tied the diff with some strong rope, onto the trolley jack cradle to stop it sliding about. Note that the rotoflex couplings will be pressing inwards against the halfshaft flanges, so you will need to gently lever them apart with a large screwdriver or pry bar, whilst lowering the diff out.

Replacing the diff is largely the reverse operation, but ensure that the spring centering blind hole on the diff case locates properly with the spring fixing 'peg' on the underside of the spring.Refit the diff mounting nuts/bolts.Then refit the diff studs and spring clamp plate. Remove the wood blocks. Refit the spring access plate. Replace prop and halfshaft bolts/nuts. Don't forget to torque up all bolts/nuts. Have a cup of tea.

 

[Mat]

I have a Mk2 Vitesse ( Rotoflex) and previously have removed/replaced the diff using a spring lifter several times in the past, but decided to try another way last time I did the job, as described below. It may sound complex, but is easier than it sounds and saves a lot of time. However, please do not attempt this method if you are in any doubt about your abilities.

 

Slightly loosen,the rear wheel nuts. Jack up the car under the diff and support on axle stands under the vertical links.Then remove the rear wheels. It's very important to position the axle stands directly under the wishbone's outer trunnion bolt 'tube' in the middle of the wishbone.  Lower the car very carefully onto the stands, checking the final resting position of the wishbones on the stands ( As the spring takes the weight,it will tend to flatten out slightly, so constantly check the stands position until the cars' full weight is safely supported. Check and check again that the car is properly and firmly supported. 

Remove the spring fixing access plate. Find a couple of bits of wood, about 2" x 2" x 3"  ( from memory) Then position these on top of the spring, directly next to the the outer edges of the spring clamp plate. You should be able to 'fiddle' these blocks into position either through the spring clamp access hole and/or reaching into the tunnel.  The idea is that the wood blocks should be a snug fit between the top leaf of the spring and the underside of the spring tunnel - to stop it moving up when you remove the spring clamp plate/nuts. Ensure that the blocks are firmly wedged in position. Then position the trolley jack under the diff to just take the weight, but no more, Do not allow it to jack the car off the axle stands. You can now remove the bolts/nuts from the halfshafts and rear propshaft flange. I found that I did not need to remove the exhaust pipe,but you might have to on a GT6. 

Now you can gradually loosen and remove the spring clamp nuts and clamp plate. Then using the double nut locking technique unscrew the studs from the top of the diff. You can cover the stud holes with masking tape to stop dirt ingress into the diff. Then remove the diff mounting front and rear nuts/bolts.The diff is now ready to come out, by gently lowering the trolley jack. As I was doing the job on my own I also tied the diff with some strong rope, onto the trolley jack cradle to stop it sliding about. Note that the rotoflex couplings will be pressing inwards against the halfshaft flanges, so you will need to gently lever them apart with a large screwdriver or pry bar, whilst lowering the diff out.

Replacing the diff is largely the reverse operation, but ensure that the spring centering blind hole on the diff case locates properly with the spring fixing 'peg' on the underside of the spring.Refit the diff mounting nuts/bolts.Then refit the diff studs and spring clamp plate. Remove the wood blocks. Refit the spring access plate. Replace prop and halfshaft bolts/nuts. Don't forget to torque up all bolts/nuts. Have a cup of tea.

Perfect advice! just done my GT6 MK3 roto using this method, worked perfect (I did need to remove the middle & rear standard exhaust) 

[trigolf]

Hi Mat,

 

Glad it worked out ok for you. 

 

Gavin

[Casper]

 

 

Non roto on a swing spring, about 2 hours on the driveway....

 

Triumph Repair Time Schedule quotes 4.2 hours for 'Differential unit, Replace.'  But then, of course, they were charging by the hour.

 

C