Help Identifying This Parts - 1984 Nissan 720 Sunrader RV

[bluexl]

Hi,

 

I needed help identifying what this rod that goes from the lower control arm to the front of the radiator support frame is. I wanted to replace the rubber bushings on it, but not sure what part it is exactly. Thanks.

 

[thisismatt]

Tension / compression (T/C) rod, radius rod.  Bushings should be available at your local auto parts store or rockauto.com

[thisismatt]

...and try to stick with a pliable rubber and not a hard polyurethane.

[Charlie69]

Summit Racing Moog parts

 

https://www.summitracing.com/parts/mog-k8122?seid=srese1&gclid=Cj0KCQiAvvKBBhCXARIsACTePW84E7espVacFn7v7Q6_RiKRt-TI-FpUGTCEJXxBGdUOfdOMtA7ja_YaAtZ9EALw_wcB

Edited March 1, 2021 by Charlie69

[datzenmike]

Find rubber ones. Poly is not very compliant and the tension needs to swing with the up and down movement of the LCA. Poly will restrict this forcing it to bend instead. Bending leads to metal fatigue. The tension rod forms one side of a triangle and locates and prevent the LCA from moving forward or more importantly... backward from the forward motion of the vehicle. Loss of the tension rod would be disastrous to steering and handling while driving.

 

 

 

 

 

 

 

[bluexl]

Thank you everyone. This is immensely helpful!

[Charlie69]

The above Summit link is wrong I am sorry.  I am trying to locate the Moog #. 

[Charlie69]

Here is the factory part # 54476-01W00 still available from Nissan special order. 

 

[thisismatt]

https://www.rockauto.com/en/partsearch/?partnum=5447601W00

[Charlie69]

Mike is correct about using the rubber over poly.  I put polly on one of my trucks and was changing it to rubber the next weekend. Too damn stiff.

[datzenmike]

[dhp123166]

On 3/1/2021 at 6:56 AM, datzenmike said:

Find rubber ones. Poly is not very compliant and the tension needs to swing with the up and down movement of the LCA. Poly will restrict this forcing it to bend instead. Bending leads to metal fatigue. The tension rod forms one side of a triangle and locates and prevent the LCA from moving forward or more importantly... backward from the forward motion of the vehicle. Loss of the tension rod would be disastrous to steering and handling while driving.

 

 

 

 

 

 

 

And excessive metal fatigue on your lower control arms will change the camber of your front wheels.

Edited March 3, 2021 by dhp123166

[dhp123166]

On 3/1/2021 at 3:05 PM, datzenmike said:

That is not a 720 tension rod.

 

Looks like an s-30 ZCAR.

 

720 tension rods are much more stout and angled.

[dhp123166]

On 3/1/2021 at 6:56 AM, datzenmike said:

Find rubber ones. Poly is not very compliant and the tension needs to swing with the up and down movement of the LCA. Poly will restrict this forcing it to bend instead. Bending leads to metal fatigue. The tension rod forms one side of a triangle and locates and prevent the LCA from moving forward or more importantly... backward from the forward motion of the vehicle. Loss of the tension rod would be disastrous to steering and handling while driving.

 

 

 

 

 

 

 

 

The total range of motion is a few degrees. 

 

Both tension rods and bushings on each are torqued down.

 

There is no "swinging" per se happening during normal operation.

 

I fail to see how poly would differ much from rubber seeing as torque for both nuts is identical.

Edited March 4, 2021 by dhp123166

[datzenmike]

1 hour ago, dhp123166 said:

That is not a 720 tension rod.

 

 

 

It's not. Only to show that they do break.

 

1 hour ago, dhp123166 said:

 

The total range of motion is a few degrees. 

 

Both tension rods and bushings on each are torqued down.

 

There is no "swinging" per se happening during normal operation.

 

I fail to see how poly would differ much from rubber seeing as torque for both nuts is identical.

 

The tension rod end at the LCA moves up and down the full range of motion of your front wheels. That's from full droop with the wheels off the ground to the full compression hitting a speed bump. Yes, driving on pavement isn't much movement, but it's accumulative. Failure is without warning.

 

https://forums.hybridz.org/topic/22762-scary-tension-rod-failure/

 

 

Drilling 6 holes in an inner circle will allow them to compress more.

 

 

 

Other disadvantages of using poly...

 

Being non compliant (solid) One face grips a part and the other slides causing squeaks and worse, wear. Rubber on the other hand is compliant and grips onto both parts and twists internally. Again, being solid, poly transmits unwanted road noise and vibration. Poly is more at home on a race track where comfort, vibration and noise is not a factor and they are inspected regularly and replaced. Something that on a road vehicle you want to avoid.

[thisismatt]

3 hours ago, dhp123166 said:

 

The total range of motion is a few degrees. 

 

Both tension rods and bushings on each are torqued down.

 

There is no "swinging" per se happening during normal operation.

 

I fail to see how poly would differ much from rubber seeing as torque for both nuts is identical.

Because there is a sleeve that takes the compression torque, not the bushing. While the bushing may/should get squeezed in the process, it's not the limiting factor in the nut tightening torque.  Hence, once the torque is applied, rubber is still more compliant.

[dhp123166]

12 hours ago, datzenmike said:

 

It's not. Only to show that they do break.

 

 

The tension rod end at the LCA moves up and down the full range of motion of your front wheels. That's from full droop with the wheels off the ground to the full compression hitting a speed bump. Yes, driving on pavement isn't much movement, but it's accumulative. Failure is without warning.

 

https://forums.hybridz.org/topic/22762-scary-tension-rod-failure/

 

 

Drilling 6 holes in an inner circle will allow them to compress more.

 

 

 

Other disadvantages of using poly...

 

Being non compliant (solid) One face grips a part and the other slides causing squeaks and worse, wear. Rubber on the other hand is compliant and grips onto both parts and twists internally. Again, being solid, poly transmits unwanted road noise and vibration. Poly is more at home on a race track where comfort, vibration and noise is not a factor and they are inspected regularly and replaced. Something that on a road vehicle you want to avoid.

But poly is not "solid".

 

It is harder than rubber but not as unyielding as steel.

 

I use poly on my 720 now and used it for years on my ZCAR with no issues other than noise.

 

In the picture you posted above look what happens to rubber over the years. That looks like much more of a safety issue than any of the allegedly possible issues created by polyurethane.

 

[dhp123166]

11 hours ago, thisismatt said:

Because there is a sleeve that takes the compression torque, not the bushing. While the bushing may/should get squeezed in the process, it's not the limiting factor in the nut tightening torque.  Hence, once the torque is applied, rubber is still more 

Word salad.

 

Torque is not the issue because in a real world comparison both t.c. rod nuts would be tightened the same.

 

I like polyurethane and I am not dissuaded by fear mongering.

 

 

 

Edited March 4, 2021 by dhp123166

[thisismatt]

12 minutes ago, dhp123166 said:

Word salad.

 

Torque is not the issue because in a real world comparison both t.c. rod nuts would be tightened the same.

 

I like polyurethane.

 

 

 

You're an idiot. 

[datzenmike]

If they work for you then you should go with them. Once they are on you're committed and it's easier to 'like' than to tear them all out. To be fair you are comparing old rubber to new poly. New rubber will surprise you.  Only place I would use poly in on the sway bar and I'll be watching them for wear. I had poly on the shackles on my truck. They were worn oval and squeaked. Never had that problem with rubber. Poly is harder and more solid than rubber. Less compressible, less compliant. The thinking is that the suspension deforms less under load and handling improved and while true there are compromises to be made in noise ride comfort and maintenance. 

[Charlie69]

51 minutes ago, dhp123166 said:

Word salad.

 

Torque is not the issue because in a real world comparison both t.c. rod nuts would be tightened the same.

 

I like polyurethane.

 

 

 

Tension control rod to frame (bushing end) the torque is 118 to 157 ft lbs.  The bolts to the control arms have a torque setting of 38 to 52 ft lbs.

 

On my trucks I torque the bolts to a torque the is in the middle of the torque range.  For example the TC rod nut is 118 to 157 so the difference is 39 so I round 39 up to 40 the nearest even number and divide by 2 giving me 20 and I add that to the low torque number of 118 which gives me the torque of 138.  To simplify this more for setting my torque wrench I again round 138 up to 140. 

 

I always torque in 3 steps meaning in this 140 ft lbs torque I torque both nuts to 100 ft lbs, then to 120, and finally to 140.  This is done with the wheels off the ground.

 

This is my method but I am sure other people just tighten them up to what "feels good" and never puts a torque wrench on them.

Edited March 4, 2021 by Charlie69

[dhp123166]

41 minutes ago, thisismatt said:

You're an idiot. 

 

You know where I live.

 

Come and have a coffee with me.

 

We can discuss it.

 

 

[Charlie69]

1 hour ago, dhp123166 said:

But poly is not "solid".

 

It is harder than rubber but not as unyielding as steel.

 

I use poly on my 720 now and used it for years on my ZCAR with no issues other than noise.

 

In the picture you posted above look what happens to rubber over the years. That looks like much more of a safety issue than any of the allegedly possible issues created by polyurethane.

 

These bushings are "wear" parts and required maintenance is replacing as needed.  Myself I prefer the rubber over poly on my trucks.  The simple changing of bushings from time to time gives me a chance to check all the other wear parts on my trucks.  This to me is just part of routine maintenance required to keep my trucks in a safe condition for driving.

[dhp123166]

1 hour ago, datzenmike said:

If they work for you then you should go with them. Once they are on you're committed and it's easier to 'like' than to tear them all out. To be fair you are comparing old rubber to new poly. New rubber will surprise you.  Only place I would use poly in on the sway bar and I'll be watching them for wear. I had poly on the shackles on my truck. They were worn oval and squeaked. Never had that problem with rubber. Poly is harder and more solid than rubber. Less compressible, less compliant. The thinking is that the suspension deforms less under load and handling improved and while true there are compromises to be made in noise ride comfort and maintenance. 

 

What I choose to use on my vehicle is not the issue.

 

The o.p. asked for help and immediately out the gate was met with ( in effect) " Don't use poly bushings because they are horribly ineffective and you will suffer catastrophic vehicle failure if you do."

 

I am just offering my anecdotal experience as opposed to theoretical hysteria.

 

O.p. should have as much info on the topic as possible to make an educated decision.

 

B.T.W. I have used new rubber and it still wears faster than polyurethane.

Edited March 4, 2021 by dhp123166

[datzenmike]

Did not say any of that in effect. There was no fear mongering or hysteria involved just risk management and information. Here it is again...

 

On 3/1/2021 at 6:56 AM, datzenmike said:

Find rubber ones. Poly is not very compliant and the tension needs to swing with the up and down movement of the LCA. Poly will restrict this forcing it to bend instead. Bending leads to metal fatigue. The tension rod forms one side of a triangle and locates and prevent the LCA from moving forward or more importantly... backward from the forward motion of the vehicle. Loss of the tension rod would be disastrous to steering and handling while driving.

 

Matt's correct....

 

3 hours ago, thisismatt said:

You're an idiot. 

 

 

 Better check your tension rod fronts regularly.