Clicking noise from rear when changing gear and taking up drive

[Martin50]

I am looking for some help, thoughts and or advice. I have a 1969 TR6 and to best of my knowledge it is mainly original. I have been using it more over last few weeks and have noticed a clicking from the rear when I take up drive. It happens when I change down gear and when I change gear with no load on the drive shafts if that makes sense. I think it has been there for quite some time - not a new symptom. But I wanted to check if this is something I can live with for awhile or if if it something to address. Is this typical? It is not a loud noise but definitely noticeable as I drive. I think the rear axle oil was changed a couple of years ago by a garage that did a service on the car, I have not checked the oil as yet but on my list to do.

The car is running well and I have just been enjoying taking it out for runs. My hope is to carry on certainly over the summer and longer if I can. This maybe a quirt of the car but thought better to ask as the knowledge in this forum is very valuable. Welcome any thoughts or tests I can do to check what it is.

[BlueTR3A-5EKT]

Wire wheels or steels?

[Martin50]

Wire wheels. Had not thought these would be a factor.

[Mike C]

Might be the universal joints. Is the noise at wheel frequency or propeller shaft frequency?

Maybe a good idea to jack up each rear when in turn and rock  it back and forth checking for noise or looseness.

 

[Martin50]

Mike, It is a once off click with no frequency. I have overhauled the rear brakes a few months ago and checked back and forth looseness. It did not seem loose at the time but wish I’d checked more. The click comes when I start to accelerate picking up drive, as a once off click. Depending on how I change gear down or up it does not always appear. My guess is the rear axle but pure guess. My worry is if it sign of a big issue. Or is there always some play in the rear axle that can be lived with?

Appreciate your reply and I will jack up rear in turn and see if I can isolate free play or noise. As I mentioned taking the TR out has been fantastic. 

Is there a tolerance for free play? Or should each rear wheel feel tight? My thought when I worked on the rear wheels / Brakes was that the each wheel would be stopped by the the other wheel on the ground - hence i was not thinking there would be any free play. So i probably wasn’t looking to closely. 

[John McCormack]

26 minutes ago, Martin50 said:

Mike, It is a once off click with no frequency. I have overhauled the rear brakes a few months ago and checked back and forth looseness. It did not seem loose at the time but wish I’d checked more. The click comes when I start to accelerate picking up drive, as a once off click. Depending on how I change gear down or up it does not always appear. My guess is the rear axle but pure guess. My worry is if it sign of a big issue. Or is there always some play in the rear axle that can be lived with?

Appreciate your reply and I will jack up rear in turn and see if I can isolate free play or noise. As I mentioned taking the TR out has been fantastic. 

Is there a tolerance for free play? Or should each rear wheel feel tight? My thought when I worked on the rear wheels / Brakes was that the each wheel would be stopped by the the other wheel on the ground - hence i was not thinking there would be any free play. So i probably wasn’t looking to closely. 

It is possible that there is wear in the hub/wheel splines. This will make a knock rather than a click but what's in a word; click/knock.

However, if it is a lighter click sound I would be confident that the differential mounts have broken away, especially the front right one. The metal edges of the crack click back and forward as the power comes on/off.

The diff will need to come out and the mounts welded up, with reinforcing. You will find plenty of descriptions online.

[Mike C]

There will be free play if you rock the jacked up wheel with the handbrake off and the engine in 4th gear. I can't put a figure on it- but it should be reasonable with no obvious noise.

Don't know if it's relevant but I had a similar intermittent click in an outboard two years ago- it was a worn dog clutch letting go under load. Do you have an O/D fitted?

[Mike C]

5 minutes ago, John McCormack said:

It is possible that there is wear in the hub/wheel splines. This will make a knock rather than a click but what's in a word; click/knock.

However, if it is a lighter click sound I would be confident that the differential mounts have broken away, especially the front right one. The metal edges of the crack click back and forward as the power comes on/off.

The diff will need to come out and the mounts welded up, with reinforcing. You will find plenty of descriptions online.

+1. Common problem and easily checked.

[Martin50]

Mike, John, thanks. I’ll need to look into this. I hadn’t thought diff mounts as a possible source. On the O/D it is fitted for 2, 3 & 4. It will take me few days before I’ll be able to check but I will update once done.

[Iruka]

Had a similar clicking noise. Found a small crack on the diff bridge, once welded no further clicking. Worth checking the bridge as well as the mounting pins.

[Chris Mountford]

Hi,

My money would be on a Universal joint breaking up. The rollers start to climb over one another causing the them to make a cracking sound ....

When all the rollers in that cup have broken up and fallen out it all goes quiet again.

I got home from the middle of France (circa 500 miles) after all the rollers had gone, My guess is it'll be the UJ inside the trailing arm (wheel end) that is impossible to grease without taking the driveshaft out.

Chris

[Drewmotty]

The steel mounting bracket bolted to the diff often cracks and causes a similar noise. 

[stuart]

29 minutes ago, Drewmotty said:

The steel mounting bracket bolted to the diff often cracks and causes a similar noise. 

Yep always a favourite to make that sort of a click.

Stuart.

[Z320]

Did you grease the kones on your wire wheel adapters (better you did not)?

How tight did you lock the octagon nuts? I recommend 300 Nm.

Against common hearsay they are not selftightening.

Cioa, Marco

Edited May 5, 2021 by Z320

[Martin50]

Folks, thank you for all the suggestions. I will need to look at each of these and check. The wire wheels are in very good condition and no wear in the splines / hubs - these are greased. The spinners are tight. My next check will be the diff mounts. I do have pretty good records of prior owners maintenance going back to 90’s. I need to trawl thru this as well but don’t recall seeing anything on the rear axle. 

Again thank you for all the input. Always fun trying to sort these issues but good sense of achievement when it is fixed. 

[Z320]

Yeah I know,

it is very popular to grease the splines. I've been told to avoid rust between them......?

Sadly by sliding the wire wheels on the adapters all grease from the splines is pushed on the cones!

Why do the splines wear out? Because the move and hit on each other (clonk-clonk).

So what is better? To have grease on the cones for best slide - or to keep them proper free from grease for a tight fit?

My advice is to clean them proper, fix the wheel - and remove it again to check and clean until there is no grease anymore on the cones.

In your case I would check this first, this is little effort.

Ciao, Marco

 

Edited May 6, 2021 by Z320

[Peter Cobbold]

As well as diff mount in chassis the pressed steel bridge bolted to diff nose can fracture near the offside pin. Single click upon taking up drive from standing.

Peter

[Martin50]

I’ve not had chance yet to look under the car. Another question: Do you think I would be able to visually see these breaks / fractures with external examination? I guess it would depend how bad they might be? Anyone’s experiences on this would be valuable if you could share.

[Z320]

you can't see everywhere, I check this points alway with my fingers (crossed until today)

btw: do you have new hubs?

Edited May 7, 2021 by Z320

[Rob Salisbury]

1 hour ago, Martin50 said:

I’ve not had chance yet to look under the car. Another question: Do you think I would be able to visually see these breaks / fractures with external examination? I guess it would depend how bad they might be? Anyone’s experiences on this would be valuable if you could share.

Hi Martin, in answer to your question the only way to be sure of all 4 chassis mounts is to remove the diff I'm afraid, if one has gone then the others will go soon after.

Welded repairs in this area are quite common and there are kits of parts to re-make the brackets, pins etc, but access to do the job properly is limited.

Cheers Rob

[Martin50]

Marco yes they the hubs are new.

Rob, thanks I was looking at this and makes sense to remove diff. Not what I wanted but suspected I had to do this.

[Z320]

Hi Martin,

me and a friend bought Good Parts new hubs some years ago,

no doubt about their quality, the big nut is secured with a notch in a ditch.

All was OK the first 1 or 2 years, then my friends rear axle started to become noisy making clonks.

It needed some time at my garage and under the car to find both hub's flanges moving on the shafts because they have not been tight anymore.

Asking the suplier he told us this can hapen and to torque them up again to 300 Nm. With this my freind's TR250 was quiet again.

After only one year he had to put the nuts off and secure it with Loctite strong because they both started to be noisy again!

Last year my rear axle started to become noisy and after a long research I remembered this and found one hub locked with only 120 Nm, the other with 150 Nm.

I torqued them up to 200 Nm and the left side is quiet now, the right side not.

Believe it or not: its one of me todays jobs to torque both up to 300 Nm with a stronger torque wrench.

You can do this through the wire wheel adapter but the wheels have to be off.

Ciao, Marco

 

Edited May 8, 2021 by Z320

[Tim D.]

Before you really start taking things apart check the tightness if the prop and driveshaft bolts. I picked up a clonk earlier in the year.. couldn’t be UJs in my case as the ones in the prop were new and I have a CV joint setup on the driveshafts. Diff bridge had been welded already and I don’t have wires. In the end I found  slightly loose bolts on the drive shaft on one side. Nipped them up and all good. No idea why they were loose.  
tim

[Z320]

Back from my garage and a test drive:

L-O-V-E-L-Y,

now you have a lot of indications for possible reasons 

Good luck!

Edited May 8, 2021 by Z320

[Martin50]

Just to follow up and update on investigations. The noise is from both rear drive shafts. There is no grease nipple so no way to pack, but there is some free play which is causing the noise “clicking” when taking up drive or when taking off throttle. I had to take to local garage to get this looked at, it was not something I could determine for myself. Fortunately they are confirming the diff mounts are good and not the source of the noise.

I’m planning to replace both rear drives. Suspect these are from original car so not bad for 50 years old. Hopefully get the fix done by early Nov. May not be many or any days to run car till next spring, but want to get it on the road asap.

Extremely difficult to describe a noise - one persons clonk is another’s click. Really appreciate everyone’s input and comments on this. Very helpful when chatting with garage. Thank you.

Regards Martin