I hit the junkyard the other day looking for some odds and end when I discovered something amazing, the Nissan 280zx has the same(almost) rear suspension as the J30. After some measuring I found that the rear struts are identical. I checked online and found new struts for as low as $32, but shipping costs defeated the savings. So I headed off to the local Checks/O'Rileys and ordered a new set of rear struts for $39.99 each and had a totally different car 2 hours later. The only difference is the 280zx strut is about 1/2 inch shorter. When I ordered the struts this is the criteria I used: 1981 280zx, targa top, non-turbo. Here are some pictures for all you non-believers!!!

Left is the old J30 and right is the 280z:



All mounted up:



All bolted up:



The J30 strut has a bushing around the bottom hole which you can see here is all blown out, but the 280 strut is solid and will not have this same problem!



I hope this will help someone, if you have any questions let me know.

Sweet !!!
Now if you can find a match for the fronts you'll be a Nico hero !!!

I checked the autozone for the front strut cartridge. Look like the 280zx has the same shape as J30. Just want to make sure the size is also same.

This is the autozone information
Extended Length: 21.36 in.
Collapsed Length: 15.65 in.
Stroke: 5.71 in.

What's your ride like with the 280 struts on the rear?
I've got an email in to Monroe to see if I can get the part number for the cartridge that they used to make for the J. If Ican get the part number I'm going to call all the local shops and hope to get lucky.(very lucky)
I also ask them if there was a cartridge that was the same size as the OEM cartridge from a simular application that we could use. I don't have much hope in this though because of the liability that it could put them under.

After searching this forum, I got these pictures from jdurrty. I hope it will help us to find the similar front strut for J30.

Ha I forgot I posted those^^ I'm still looking for a suitable replacement for the fronts. As for the ride with the 280 struts, they ride amazing!!! With 265's in the rear, I had tracking problems to begin with and useless struts didn't help the situation anymore. With the new struts I'm actually looking for potholes to hit because I cant feel them anymore and it corners like a champ now! Easily the best $80 I've ever spent on my car

jdurrty wrote:Ha I forgot I posted those^^ I'm still looking for a suitable replacement for the fronts. As for the ride with the 280 struts, they ride amazing!!! With 265's in the rear, I had tracking problems to begin with and useless struts didn't help the situation anymore. With the new struts I'm actually looking for potholes to hit because I cant feel them anymore and it corners like a champ now! Easily the best $80 I've ever spent on my car

I think you still has the front strut size. Please compare it to 280ZX front strut. Let us know.

2 left at Rockauto.com for 45.00'ish shipped !!
That's for two rears ~~
Get em while you can !!!

Well I heard back from Monroe and no luck on the old part number or them recommending an alternative cartridge. He did tell me that they have a database of the size specs on all of their current products. So If we can get the measurement off of an OEM strut cartridge we should be able to match it up with some thing that will work.

http://www.monroe.com/catalog/documents ... hSheet.pdf

Page 16 starts the strut cartridge specs.

EDIT: JDURRTY, If you can compare this to the front cartridge that you have and see how it matches up.:
Monroe cartridge insert # 73229
Body Length 14.000"
Compressed Length 14.500"
Extended Length 20.625"
Travel 6.125"
This is from the front of a 89 300ZX NA. If this matches up we should be able to use any brand of insert that will fit the front of a 89 300ZX, shouldn't we?

Need to get a caliper on a J cartridge to be sure the diameter is dead on.
Also from looking at JDURTYS pic there's a lip on the top of the strut cartridge.

yodawill2000 wrote:Need to get a caliper on a J cartridge to be sure the diameter is dead on.
Also from looking at JDURTYS pic there's a lip on the top of the strut cartridge.

Your post got me to thinking about the replacements for sale on Ebay. When you look at those, they do not look like the originals either.

I agree
And the price is higher than OEM at everythinginfiniti.com
I'm just worried about buying them from Joe because they have been on the shelf for Uber years !!

NASCARLANCE wrote:Page 16 starts the strut cartridge specs.

EDIT: JDURRTY, If you can compare this to the front cartridge that you have and see how it matches up.:
Monroe cartridge insert # 73229
Body Length 14.000"
Compressed Length 14.500"
Extended Length 20.625"
Travel 6.125"
This is from the front of a 89 300ZX NA. If this matches up we should be able to use any brand of insert that will fit the front of a 89 300ZX, shouldn't we?

I measured everything up and the closest strut I could find was part# 73245, but even this one uses the wrong shaft size. The shaft size (measured in purple below) of the J30 is nearly 1" thick where as the 300zx is only 3/4". I don't think the 300zx strut will work unless you can find a retaining nut from a 300zx and hope it threads into the J30 strut to accommodate for the smaller shaft size. Here is the strut insert measured out below. I had to extend the strut out a bit to make room for all of the measurements so, the green 1" shows how much of the shaft sticks out of the strut tube when fully compressed. The extended and compressed measurements are that of the shaft only and do not include the top 2.5" worth of threads at the top. I hope this somehow helps

Good job !!!
1 step closer to finding a match !!

what is the next step? did anyone find a matched one ?

newboy1 wrote:what is the next step? did anyone find a matched one ?

I might actually go with the 300zx strut insert. Granted there is 1.5" less of travel, my measurements indicate this will end up lowering the car and inch or two. Hopefully this will be a cheaper alternative to swimshark's total coil-over conversion. I am in the process of converting the old strut insert into a ghetto-rigged air-ride insert. I'll let you know how it goes.

Gonna be swapping out the rears this weekend.
Any tips on the swap or is it pretty straight forward ?
There was a post awhile back that I cant find that said it can be done pretty easy with two jacks instead of a spring compressor.

Yeah it was fairly easy, at least for me that is. I have done many suspension jobs in the past and have my own strut spring compressor, so I had it done within an hour. I haven't heard of anyone using jacks to compress a strut and quite frankly it sounds very dangerous especially with how tight the springs are compressed on the rear strut. Any chain of auto stores will have spring compressors you can rent for free. This will save you time, and some fingers! There really wasn't any secret to putting these struts together other than how many bushings you want to put in to adjust the ride height. Below is a picture of the order of washers and bushings that I used first starting with the gold washer in the top left corner and finishing with the bolt in the bottom right. These combined with tightening the top bolt down all the way lowered my car about 1.5" which is what I wanted. Let me know if you have any other questions!

Sweet.
Thanks J.
I'll pick up a compressor set tomorrow and get er' done.
I will need it for the front someday soon anyway.

A Tip for anybody else doing this.
As the FSM mentions Mark the top hat, spring, ect before taking the assembly apart.
First side I didn't and the bottom wasn't even close to lined up with the shaft.

Got real good at using the spring compressors though !!!

How's your ride now Yoda?

BIG difference in the rear but I still need to rehab the front.
The old shocks weren't completely blown but the dust cover bellows were gone.
And just like JDurrtys the lower bushing was worn way out.

Did you find a way to replace the front strut?

jdurrty wrote:

newboy1 wrote:what is the next step? did anyone find a matched one ?

I might actually go with the 300zx strut insert. Granted there is 1.5" less of travel, my measurements indicate this will end up lowering the car and inch or two. Hopefully this will be a cheaper alternative to swimshark's total coil-over conversion. I am in the process of converting the old strut insert into a ghetto-rigged air-ride insert. I'll let you know how it goes.

Well i am about to take the plunge and buy the 1989 300ZX inserts for the front Strut assembly...This is the one i am planning to purchase...willl tell you all how it goes!!

http://www.autopartswarehouse.com/detai ... 44968.html

Please do !!
Do you you know the Diameter of those inserts ??

i am trying to find out...still searching though...will let you all know as soon as i find out

Somehow I think that lip around the top of the OEM strut cartridge has a purpose.

Does it rest on the top of the strut tube ??

It acts as a spacer between the strut insert and the outside tube it fits in. The outside diameter of the insert is 1.5" whereas the inside diameter of the tube it fits in is 1.875." That lip prevents the insert from flopping around inside the tube.