Gearbox MUCH quieter.

[littlepippin]

Last year I had to have a new gearbox mount fitted for the MOT, and it was one of those after market, made of concrete ones. Ever since, the gearbox has sounded SO noisy that it seemed like every bearing was about to seize up, and the whole box was knackered and needed replacing.

Any how, today I got under neath, and fitted 4 x poly bushes to the cross member (between the cross member and the actual floor of the car) where the 4 x studs are.

Blimey - its like having a new gearbox, it is so much quieter, and the car seems even nicer to drive. In fact, like a new car ! (slight exageration there, but anyway)

Cost ? £4 for a bag of 8. They were too high at 25mm, so I cut them in half.

[Howard722]

I too had similar experience with the awful racket when I tried a new mouting!!-big mistake--I put the old one back after I giving it the once over, just wasted some money.
Surely there has to be a proper solution without resorting to poly-spacers.

[littlepippin]

Yeah, I know it is a bit Heath-Robinson, but it works. I read on this site someone said that the aftermarket ones are for TR7 and TR8 so are extra tough for the more powerful V8.
Doesn't make sense to me, surely it just is there to carry the weight ? No rotational or lateral torque on it surely ?

[DNK]

HMMMMM!

[littlepippin]

Yes Don, sorry I know I should have took some piccies, I thought that when I did the post. Next time I'm under I'll take a shot or two, but If you are familiar with the oily side of the TR7 You will probably know exactly what I'm on about ?

I am doing it out on the street basically, so just got in and out as quick as possible......

[Hasbeen]

It is a resonance thing.

When I bought one of my 7s I thought the gearbox was shot. Dreadful mechanical disintegration noise in the cabin. I rang our Queensland Triumph specialist to ask if parts were readily available. He laughed & told me to check the rubber gearbox mount had not collapsed completely, or that the steel spacer between the mount & the box was not missing.

The spacer was missing, & the rubber mount had turned to jelly. The box was sitting on the steel subframe, & all the mechanical noise was being transmitted to the body, which acts as an amplifier. Spacer replaced, & a new mount, & peace returned.

When I went in to pick up a used spacer he had in stock, he told me he had recently had a 7 shipped down from Rockhampton, over 600 kilometres to our north, for a gearbox rebuild, which simply had the same problem.

These early monocoques really do resonate. Your hard new mount was transmitting all the noise.

Hasbeen

[dursleyman]

I put new engine and gearbox mounts on my car when I swapped the engine few years back and regretted it immediately. Luckily the old ones were not in too bad condition so I swapped them back first chance I got. Result is smooth running restored.
The TWOA guys have investigated this subject quite a bit and found the modern ones have much harder rubber and the metal insert is also a different shape. Old ones have an inverted wedge (!) shape so they sit in the softer rubber nicely. New ones are a parallel sided block and are bonded tighter to harder rubber so no hope of absorbing noise/vibration.
They also investigated using a Volvo mount which is similar and may be an option.
I will try to find the article and post it here.

Try this:- https://drive.google.com/open?id=0Bz1MK ... VR2MkIxVUE

[busheytrader]

I bought what I thought was the Volvo alternative some time back.......but it was the wrong shape.........

[Howard722]

Yes I have seen old posts about a Volvo alternative mounting and if you search the `net you can see some that look very similar (740/940?) but are they likely to be `rock hardo rubber`again or are they the real deal --and do they fit??
Methinks I`ll dig out the new one I ripped out in disgust from the box of `just in case spares`and take a trip sometime to GSF Parts shop and see what transpires by way of comparison--ps. all my spacers, washers and bolts are all in the correct place it`s just the `new` mounting that is/was the issue!

[dursleyman]

Found this article on the Dolomite page, they use the same TKC1044 mount and have the same problem with modern ones being too hard. One of their guys wrote up how he used a Volvo 740 automatic mount and it worked pretty well.

https://drive.google.com/open?id=0Bz1MK ... 2JybkJ1aFE

[REPLIC8]

I did exactly the same thing on my TR8, but I used 4 old rubber bushes from the rear shocks between the cross member and the body. The transformation is quite remarkable. I haven't done it on my green TR7 as I want to keep it factory standard, but I'll definitely be doing a similar thing on our next project.

[busheytrader]

I bought what I thought was the Volvo alternative some time back.......but it was the wrong shape.........

The mount I ordered was the same, FEBI 22394 but it looked so different I put it to one side. I can't remember where it is now since the garage is full of dismantled Mini Cooper......

[littlepippin]

Well, I think the preferred fix would be to unearth some original "new old stock" mounts and fit one, but this temporary fix is so cheap and easy to do - 20 Minutes. Would recommend using nylock nuts, and tightening them up enough to compress the bush by about a third. No movement only insulation.
I think a lengthy test drive, and then a double check that everything is still safe and secure would be in order.

[Hasbeen]

I did once see a 7 which, with a modification of the gearbox subframe, used the Stag twin bush mounting system. It is a long time ago, & can't remember it well, but it looked Stag.

Silent block make a range of bushes for that system with different hardness. Might be worth a look.

I haven't had much luck with new old stock rubber parts. They are well aged, & haven't lasted long for me, when put to work.

Hasbeen

[supercass]

I believe one problem is that customers put up with this. If everyone who purchased this item demanded their money back (fitness for purpose etc.) a modified and more suitable part would probably be made. After all it is not rocket science! supercass