Original replacement shock absorbers

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MaddMike

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1971 Mustang Mach 1: 351 C (modified), FMX trans (modified), 9" 3:25 traction lock rear gear. I have owned this car 44 years, since I was 17.
I am tired of getting banged and bounced around on stiff performance shock absorbers. It is time to change back / over to a comfortable smooth ride. what shocks should I aim for - I am thinking Monroe or Gabriel but is there a standard original replacement and what should I look for specifically?
 
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I'm currently using KYB Gas-A-Just shocks back and front, BUT I am switching them to KYB Excel GR2, which are supposed to be one step softer and closer to original specs. KYB are either made in Japan or Mexico. If you go with KYB, buy off Rock Auto would be my suggestion. Depending on you budget of course, there a lots of very good, but more expensive choices out there. It all depends on what you want for YOUR car.
I find the Gas-A-Just a bit too hard and why I'm going to 'swap and compare', then decide which will stay on the car..
Also, it might be possible the suspension is in need of some upgrades or rework.
 
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1972 Mustang convertible, 351C 2V with FMX (#'s matching)
Currently equipped with 351C 4V 4BM, .060 over, roller cam, Sanderson block huggers, -AC
I am tired of getting banged and bounced around on stiff performance shock absorbers. It is time to change back / over to a comfortable smooth ride. what shocks should I aim for - I am thinking Monroe or Gabriel but is there a standard original replacement and what should I look for specifically?
I went with QA1's SA and run #6 setting in front (now without FMX/AC and running a 3 row alum radiator. # 4 in rear and she squats nicely on launch with 3.5 leafs and no wheel hop.
 

Hemikiller

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Currently running KYB Excel-G. Dirt cheap and the ride is about as good as a Mustang can deliver *without* spending $150+ per shock.


IMO, the best compromise between a street performance shock vs price is the Bilsteins from Street or Track. About $500/set.


 
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Currently running KYB Excel-G. Dirt cheap and the ride is about as good as a Mustang can deliver.

Hemikiller, yes those are what I meant, Excel-G not GR2, which was the previous name for that shock.
I'll be putting mine on as soon as I can work in the driveway without snow, wind or rain!!
 
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I'm currently using KYB Gas-A-Just shocks back and front, BUT I am switching them to KYB Excel GR2, which are supposed to be one step softer and closer to original specs. KYB are either made in Japan or Mexico. If you go with KYB, buy off Rock Auto would be my suggestion. Depending on you budget of course, there a lots of very good, but more expensive choices out there. It all depends on what you want for YOUR car.
I find the Gas-A-Just a bit too hard and why I'm going to 'swap and compare', then decide which will stay on the car..
Also, it might be possible the suspension is in need of some upgrades or rework.
What is the PN of the front KYB's you're running?

I recently installed a pair of KG4504 up front and KG5517's in the rear. These are the Gas-A-Just from KYB. With the car jacked up, the shocks bushings are right at 1" short of the upper shock mount. Did you have this issue?

I got these from RA and this is the only set of Gas-A-Just they list. KYB's web page shows this to be the correct PN, but I found an alternate that appears to be longer. Unfortunately (for me), I've already tossed the boxes....I had an old set of extenders, so I'm going to test the fitment with them installed. The main concern is that they'll bottom out.

Don't mean to hijack OP's thread, but felt this was relevant to his choice in shocks....may want to look at the alternate PN for our cars.
 
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What is the PN of the front KYB's you're running?

I recently installed a pair of KG4504 up front and KG5517's in the rear. These are the Gas-A-Just from KYB. With the car jacked up, the shocks bushings are right at 1" short of the upper shock mount. Did you have this issue?

I got these from RA and this is the only set of Gas-A-Just they list. KYB's web page shows this to be the correct PN, but I found an alternate that appears to be longer. Unfortunately (for me), I've already tossed the boxes....I had an old set of extenders, so I'm going to test the fitment with them installed. The main concern is that they'll bottom out.

Don't mean to hijack OP's thread, but felt this was relevant to his choice in shocks....may want to look at the alternate PN for our cars.
The shocks I just bought are; KYB343156 and KYB 343219. I too hope they are correct. I don't recall any fitment issues with the Gas-A-Just, but I'll for sure let everyone know once I get them done, hopefully in the next few days. My car has staggered shocks, so as a tip, I remove the back seat back as it just makes it easier to get to the right side shock nuts.
On the front, we should ALWAYS use a block between the frame and suspension to stop it dropping to full extension. With this done, the shock should not pull through the top mount or hang the entire suspension weight on it. A piece of 2x4 will work for this.
I also added an extra thick 3/8" washer UNDER the shaped metal cap piece and that helped take up a little extra length.
On the rear, I had been getting a heavy "clunk" and that may possible be the shock bottoming out. That was a good point for me to look at.
Hope that helps all concerned.
 
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T.
On the front, we should ALWAYS use a block between the frame and suspension to stop it dropping to full extension. With this done, the shock should not pull through the top mount or hang the entire suspension weight on it. A piece of 2x4 will work for this.
I think the block is the solution I'll go with. The Ford Repair Manual shows the home-made tool below, but if a simple wood block works, I'm all about the simple solution. I just read through a couple of other threads on this same issue.

1650639732044.png
 

Hemikiller

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What is the PN of the front KYB's you're running?

I recently installed a pair of KG4504 up front and KG5517's in the rear. These are the Gas-A-Just from KYB. With the car jacked up, the shocks bushings are right at 1" short of the upper shock mount. Did you have this issue?

I got these from RA and this is the only set of Gas-A-Just they list. KYB's web page shows this to be the correct PN, but I found an alternate that appears to be longer. Unfortunately (for me), I've already tossed the boxes....I had an old set of extenders, so I'm going to test the fitment with them installed. The main concern is that they'll bottom out.

Don't mean to hijack OP's thread, but felt this was relevant to his choice in shocks....may want to look at the alternate PN for our cars.

The KYB Gas A Justs that KYB calls out for the 71-73 Mustangs are an inch too short. You need to use the 70-71 Torino front shocks - KG4505. If you compare the extended lengths of the three below, it's obvious. There's over 1 1/12" length difference between the Mustang GaJ and the Excel.

Torino

Mustang

Excel-G
 
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The KYB Gas A Justs that KYB calls out for the 71-73 Mustangs are an inch too short. You need to use the 70-71 Torino front shocks - KG4505. If you compare the extended lengths of the three below, it's obvious. There's over 1 1/12" length difference between the Mustang GaJ and the Excel.

Torino

Mustang

Excel-G
Thanks Hemi, I have an NOS set of Motorcraft front shocks, D1ZZ-18124-E to compare them with. For sure, I'll check the GaJ's and the Excel-G and compare to my NOS set. good to know, thanks.
Looking at the size differences between the Torino and Mustang, I have to conclude that the newer Excel-G are now more of a one size fit's all as they are so close the Torino. The Excel-G's might be too long for the Mustang???

EDIT: I took a couple of pics of the NOS H/D shocks compared with a new Excel-G. What I see is the barrel length is about 3/4" longer on the Excel and the full extension is about 1" longer. The overall length is about the same difference.
So, if I'm right, the longer 'stroke' means nothing, but the 3/4" barrel length might cause an issue as that might be what is hitting when fully compressed. That is what I will look carefully at, especially on the rears. Unfortunately, I have nothing to compare that to.
I hope this is not too confusing to others.
 

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Joined
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The KYB Gas A Justs that KYB calls out for the 71-73 Mustangs are an inch too short. You need to use the 70-71 Torino front shocks - KG4505. If you compare the extended lengths of the three below, it's obvious. There's over 1 1/12" length difference between the Mustang GaJ and the Excel.

Torino

Mustang

Excel-G
Yep, the 4505's are the "alternate" PN I noted in my post. Interesting that KYB replied to one of our members (in a related thread) saying the shorter length was intentional and related to the higher damping of this model.
 
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I think the block is the solution I'll go with. The Ford Repair Manual shows the home-made tool below, but if a simple wood block works, I'm all about the simple solution. I just read through a couple of other threads on this same issue.

View attachment 62598
I bought one of these tools on eBay and I cannot get it to work with the stock sway bar in place. When you try to position it as is shown in this diagram, it will not go in as the sway bar is in the way. Here is the one I bought:
 
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I bought one of these tools on eBay and I cannot get it to work with the stock sway bar in place. When you try to position it as is shown in this diagram, it will not go in as the sway bar is in the way. Here is the one I bought:
Good to know, thanks for the info.
 
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I replaced the shocks (rear factory 50yr old) and fronts (monroe who knows how old) that were just along for the ride... Past two owners never wanted to remove the rear seat back... it was cool finding 50 yr old dust under the seat cushion :) Nice thing is with such low mileage and garaged, everything just fell out when the bolts were removed. Replaced them with KYB Gas-a-Justs from Rock Auto $150 for 4 after the $25 rebate... Always check traditional sites before ordering from CJ and the like... There are just some things you can't find anywhere else but those sites, but some stuff is still readily available.

And the ride... one forgets how much shocks effect the whole car... ( thinking back to shock ads in the 60's and 70's "replace every 20,000 mile" I thought my brakes needed adjusting before but it was all shock related. She is still not so fond of potholes but the ride is like memory lane with a car that really is like a 2 yr old car that in actuality is 50 yrs old.,
 
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SteveO_71

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I bought one of these tools on eBay and I cannot get it to work with the stock sway bar in place. When you try to position it as is shown in this diagram, it will not go in as the sway bar is in the way. Here is the one I bought:

Are the measurements of the ebay one the same as the picture in the manual? Is your sway bar original or aftermarket?
 
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I replaced the shocks (rear factory 50yr old) and fronts (monroe who knows how old) that were just along for the ride... Past two owners never wanted to remove the rear seat back... it was cool finding 50 yr old dust under the seat cushion :) Nice thing is with such low mileage and garaged, everything just fell out when the bolts were removed. Replaced them with KYB Gas-a-Justs from Rock Auto $150 for 4 after the $25 rebate... Always check traditional sites before ordering from CJ and the like... There are just some things you can't find anywhere else but those sites, but some stuff is still readily available.

And the ride... one forgets how much shocks effect the whole car... ( thinking back to shock ads in the 60's and 70's "replace every 20,000 mile" I thought my brakes needed adjusting before but it was all shock related. She is still not so fond of potholes but the ride is like memory lane with a car that really is like a 2 yr old car that in actuality is 50 yrs old.,
IF you still happen to have those rear shocks that you presume are the factory ones, could you do me/us a favor and measure the barrel length and the extended length as well if possible, post some pictures. This would be a great comparison against the KYB GaJ's or Excel-G or other brands available.
Thanks.
 
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My apologies to MaddMike for over extending his thread, BUT it has raised questions that I am dealing with, namely KYB Excel-G shocks on the front.
I started by removing one front shock to compare to the Gas-a-Just shocks currently on my car. The part numbers I bought seem to be correct, however, the Excel-G's are longer by over 1". That said the stoke is also 1" more at 5", so as the Gaj's are only using about 3" of stoke, I don't see that as a problem. However as I mentioned before when comparing the NOS shocks I have to the Excel's, the body length is also 1/2" long than the Gaj's. That would be my concern, will the shock body hit the underside of the cap? I tried to use a jack under the front disc to lift the suspension through it's full travel, but alas, it started to lift the car before it got that far. I'm thinking that as these shocks are pretty inexpensive and rather than send them back, I'll install them and see what happens. One thing I did learn with the extra travel length, one can lower the suspension all the way and it will not pull the rubbers through the top cap. However, I think I would still either use a jack carefully placed under the front disc or drum, or use a support of some sort. Here I used a piece of 2x4, but found it in the way to get to the nuts at the bottom of the shocks.
Here are some pics I hope will explain this rambling.
Pic 1, looking a shock cylinder. 2, a dust line is visible approx 2 3/4' from the cylinder, indicating the cylinder is not hitting the cap. 3, the two lengths compared, 4, a dust line is visible 3" from the cylinder top. 5, using an extra 2 3/8" washers to stop nuts bottoming out on the threads. 6, Nut tightened, so about 3/4" to tighten the cap down. NOTE: I'm temporarily using the old rubbers until I decide to install or return them. 7, jack and block. 8, NOS versus Gas-a-Just, exact same length. 9, Excel G fully extended.
I decided to fully install the Excel's on the front only so far. They actually went in without a problem. I was a bit concerned about the 1/2" long cylinder, but in effect, there was an inch of the Gaj's stroke that was unused, now there will be a 1/2". As long as the shock cylinder doesn't hit the cap, all will be good.
I took the car out for it's first drive after and I was impressed with the softer front end, no more thumping going over railroad tracks and bumps. Next will be the rears maybe tomorrow. I'll update when done.
I also went to KYB's website and the part numbers are correct for the Excel-G's and the Gas-A-Just for the 71-73 Mustang.
 

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