TR6 GoodParts Adjustable Trailing Arm Brackets TR6

[mallard]

I've had Richards brackets on my car for around 6 years with great results. Just this past winter I started to notice a clunk from the rear of the car. After inspection there are no broken welds, mounts, loose shocks or bolts, binding axles, or deteriorated bushings. The bushings are all Nylatron, swing arms and Diff mounts. I have the original mounting instructions but information on the spacers between brackets and the bushings are a bit vague. If I grab the arms and try to move it side to side I have no deflection. This seems to be the only area that may be causing the clunking sound. I checked his site for a more updated and detailed instructions but nothing could be found.

I never had to do any repair to the differential other than oil changes, and seals. I don't think the differential is my problem.

Has anybody with these mounts had the same problem?

I forgot to mention no bad u-joints.

 

[poolboy]

So you don't have the stock differntial mounts ?
Moss # 680-075

 

[mallard]

My mistake the differential mounts are BPNW Poly Bushings.

 

[tdskip]

I get a thunk on mine as well - not sure why. Doesn't seem to impact the handling.

My pins are fine and bushings are new, mounts have been boxed.

 

[hondo402000]

have you checked your shocks, if you still have the lever shocks they can work loose and give a thunk too. Check the bolts tighten to 60 ftpounds

Hondo

 

[mallard]

At the time I had tube shocks on the rear, but I'm swithching back to the lever arm shocks now. All the brackets were secure. I'm going out to the garage now to explore further into the problem. Could one of the axles developed some end play? I never had to do anything to the axles, they have less than 30K on them.

 

[vagt6]

Keith, could it be your U-joint?

Get the car up into the air (safely with jackstands, etc.) and grab the Ujoint and try to move it. Any excessive play? Clunking?

Had a clunking noise on my GT6, it was the Ujoint. Easy fix.

Let us know . . .

 

[rooster]

While you are under there check the right front diff mount.

 

[pacotaco]

Just wondering why you are going back to lever shocks after installing the tube shock conversion? I have my TR4A IRS frame almost ready to sandblast and thought I would install the conversion when I put it back together.

 

[mallard]

I like to keep things more original now than when I restored the car. I also did not see much of an improvement over the lever arm setup. There is also the risk of frame damage if your frame is not in top notch condition. If you go with the tube shocks I would look into strenghtening the shock mount on the frame. It would be very easy for you to do since your frame has been blasted.

As for all the advice I got on what to look for with my problem all ideas checked out to be fine. The only change was one spacer washer size was increased. Greased things up and put it back together with the lever shocks.

 

[TR6BobNF]

Anybody running tube shock conversion of this type should consider Bob Danielson's reinforcing brackets. This guy has a nice modified TR6 that has been featured in Hemmings Sports and Exotics magazine and he is pretty handy with TR6 improvements. Here is the link to his site that he shares freely with all TR6 owners.
https://tr6.danielsonfamily.org/BlindMoose2.htm
I am in the process of making the brackets this week.
Cheers,

 

[BobbyD]

Just because it doesn't look like a cracked diff mount doesn't mean it isn't cracked. Did you wire brush the mounts to expose any hair line cracks? A clunk doesn't need a gaping separation. Here's what my mounts looked like after wire brushing them. This litsy bitsy line was enough to cause a crack.

My personal opinion is that every TR6 needs tohave the diff mounts boxed in because at some point they WILL crack and clunk.

 

[mallard]

I agree with you 100% Bob. After I had my frame blasted during the restoration I discovered the same type of cracks in your pictures. At the time I did not have a welder so I took the frame with the TRF boxing kit and some large washers and had them welded in place at one of the local fab shops. I did not drop the differential this time but I don't think I have any cracks in any of the mounts. I hope to have the carbs adjusted this weekend and test drive the car. I don't have any good pictures of the frame because I did not have a digital camera at the time.

 

[rooster]

Hi,

I had my diff mount repaired to fix a crack a couple of years after purchasing my car. Then about 5 years after that it cracked again. It's worth taking a close look at it.

BTW, boxing it in isn't always enough to fix it. In my case I had to get a plate of steel welded on top of the frame where the pin inserts into it. The pin was put into a hole in the plate and welded. The pin sticks out a bit less than original but it is a lot more secure. I haven't had a problem with it since.

Cheers

 

[pacotaco]

Just got my frame home from sandblasting and found I do have a crack all the way across the right front differential bracket. Can I just weld that crack and box it in with the reinforcing plates I just got from TRF or do I need to order a new bracket and pin? Also found that the bracket on the front lower A frame was cracked where the single bolt attaches to the suspension (TR4A IRS) some but I also got the reinforcing plates from TRF.