Honda Insight Forum banner

Rear Shock Replacement-My Version

1 reading
152K views 308 replies 66 participants last post by  Willie Williford  
#1 · (Edited)
***FINAL EDIT (I hope) If you have previously read this how-to please note that step 12 has been added due to an oversight ( Thanks 02:)) Sorry folks***

Hello everyone:) I finished this project yesterday but had to wait until I had some free time to post. After doing some research Saturday night regarding drilling rubber and even Googling "expanding rubber bushings" I was lead to a few 4x4 forums and was given an even better idea of fabricating bar-pin mounts for the fresh Monroe 5752 shock. This way the integrity of the bushing is intact and there is no need to tear apart your old Honda shock saving time!!!

It was quite an easy job and after completing the first the second one took me all of 30 minutes from beginning to it being mounted on the car. So figure 1-2 hours depending on your tools, skill, etc.

I drive a car-hauler for a living and ran it by the shop foreman this morning. To my amazement he told me that they used to fabricate bar-pin mounts for "The Race Car" some years back out of bar stock. When I asked him how he thought these would hold up he said that as the car is so light there should be no problems. Additionally I see the tubing used for off-road 4x4's and this isn't much different.

The Monroe 5752 is labeled on the box as a light truck shock. After a long test drive yesterday I feel that the dampening is way better. The car corners well, doesn't skip on curves anymore (though I had a broken shock), and the bumps don't seem to be so jolting.

As this has been a group effort IMO thanks to all who have done the research as I am a new comer to this topic and thanks for this forum and letting me contribute my two cents:)
 
#2 · (Edited)
For this project you will need:

2 Monroe 5752 shocks (bought mine at Advance Auto) $22.99

2 6" length of 3/8 galvanized pipe (don't get gas as I believe it's cast) $9.00

2 2" nipples of 3/8 galvanized pipe $8.00

A piece of thin tough plastic like from a laundry soap or oil bottle will do the trick

Vice Grips, WD-40, 5lb sledge hammer, 3/8" drill bit and drill, and a hard raised surface (I used a 25lb barbell weight), a hack saw



1)Remove your old shocks.

2)Saw off the threaded ends of the pipe. It's too long to fit between the humps and I didn't want to drill through the weaker thread part.



3)Using the hammer flatten one end of the pipe about 1"-1 1/2" give or take.



 
#3 · (Edited)
4)Lube up the hole in the shock with WD-40 and insert the round end into the TOP shock hole. Leave it offset to one side (you can center it again after the next step).





5)On the hard surface flatten down the other end with the hammer making sure to keep the same angle as the other end. Then center the mount.





As you see it's not perfect and doesn't have to be. The mounting/tightening will take care of that.
 
#4 · (Edited)
6)Now drill your holes. I estimated the distance from the side ( I guess it's about 1/2") then then using a punch marked the spot and then measured approximately 2 3/4" and marked the other spot. I put a block of wood underneath and lubed it with WD-40 once or twice 'peck drilling' (pressure then no pressure then pressure etc) the hole. Then make the holes a bit sloppy with the drill because I know my measurements weren't exactly "ON".

CAUTION: As the drill get's ready to break through the outer pipe wall it may catch and rip either the pipe/drill from your hand or spin around. Make sure your drill is TIGHT in the chuck.





7)Lube up the bottom hole with WD-40 and insert the 2" nipple. This replaces the old bottom mount with no need for shimming.

 
#5 · (Edited)
8)Ready to mount!



9)I found starting the outboard bolt 1st then using an extension to align the inboard bolt worked best. Leave it LOOSE!



10)Using vice-grips bend the bottom tab that isn't the nut plate just a bit to accommodate the 2" nipple (it's just a tiny bit longer than the original Honda mount). Align then start that bolt.

 
#6 · (Edited)
11)Now tighten the piss out of the two top mount bolts! The bar-pin metal should flatten out and be pinched between the bolts eliminating all sloppiness. It is not necessary to tighten the bottom bolt at this point.

12)NEW STEP-DIELECTRIC INSTALLATION
(You can try to do it all at once without step 11 first but my feeling is that you will tear the plastic without knowing resulting in corrosion)

***Due to the use of dissimilar metals (aluminum and steel) a dielectric is required between the mount and the car body to prevent corrosion of the body. A small piece of thin tough plastic between the contact points will do the trick. Example: If you have a plastic notebook binder you can cut that up. Or a plastic oil container. Laundry soap bottle.***
http://en.wikipedia.org/wiki/Galvanic_corrosion


Remove the shock again now that you have bent the metal into place. I used an oil 1qt oil bottle as a plastic dielectric source. I just cut the side out then cut that into 4 squares, drilled a hole and trimmed it to fit. Easy...








13) Tighten all bolts.
You're done... Nice Job!!!

 
#7 ·
You list the Monroe 5752, but searching reveals several variations. For example one has a t bar at the top. Are there any additional designations on the number or a specific link?
 
#8 · (Edited)
I don't know as I am not at home. I bought them from Advance Auto Parts and to be honest I expected the bar-pin in the shock but was pleasantly surprised it wasn't. There weren't any spacers in the shock mount either... Just a rubber bushing:D

Did I get lucky? IDK!!!

The only reason I know about using the 5752 was because of the research done by http://www.insightcentral.net/forums/members/02insight.html. I originally tried a Gabriel so called equivalent from AutoZone but it bottomed out. Thanks 02!!!
 
#11 · (Edited)
Holy crap Homer! This is awesome! This looks like something anyone can do! Thanks for taking the plunge and actually doing this!

I know what I'll be doing once my Insight reaches 100k miles! :D
Next time you see a gas guzzling 4x4 Jeep thank them. I just took something they have been doing obviously quite awhile and applied it.

I guess it IS a Jeep thing!!! Sometimes... LOL!
 
#10 ·
I had been watching that other thread and waiting for something definitive. Just ordered two on Amazon at $16.23 each with free shipping.
 
#15 ·
Curiosity question - are washers needed on the bottom to prevent the shock from sliding from side to side on the 3/8" pipe? Is this even a concern?
 
#16 ·
By the way, thank you for the great 'how to'!! I also just ordered a pair of these on Amazon and plan on installing them in the next couple weeks.
 
#17 ·
Thank you.
This is definitely easier than trying to remove the mounts from old shocks and forcing them in the monroe's. I am definitely going to try this.

I am a little concerned about the strength of the top mount made of pipe. If it is soft enough to be beat flat with a hammer, I wonder if it can withstand the abuse of the roads. Probably unlikely since the car is so light, but it still makes me wonder why the original honda ones are so thick. Even thicker than similar ones I have seen on other shocks.
 
#22 ·
I am a little concerned about the strength of the top mount made of pipe. If it is soft enough to be beat flat with a hammer, I wonder if it can withstand the abuse of the roads. Probably unlikely since the car is so light, but it still makes me wonder why the original honda ones are so thick. Even thicker than similar ones I have seen on other shocks.
After reading this this morning I had a 5 hour drive home and suddenly SSGT Norm M from my Air Force days saying in the back of my mind, "They're Dissimilar Metals!" Oh yeah, the Insight is aluminum. Steel and aluminum don't mix.

Galvanic corrosion - Wikipedia, the free encyclopedia

This is why the mount is so large. Honda opted for aluminum to aluminum and for an aluminum mount to be strong enough it has to be cast and HUGE!

As for the strength of the pipe? Here is a stainless 4x4 bar-pin mount. It's rolled stainless steel. Not much difference IMO.

http://www.higherground4x4.com/Tech/JKS/broken_shock_pin.jpg

So when I got home today I put the car up on the ramps and everything looks nice and tight. Nothing even close to being stressed.

BUT, the problem of the steel against the aluminum body needs to be addressed. I spoke with the shop lead man today before coming home and he told me that aluminum against steel is common on tractor trailer car-haul rigs and all that's required is a dielectric between them. The wiki article explains it too. He told me that it's just usually a piece of thin somewhat hard pliable plastic, say like a plastic notebook binder cover. Once it's bolted in place it won't move and that will be that.

He also told me that the rubber bushing allows for pressure, twisting, etc. on the mount and therefore it shouldn't break or bend.

As an extra measure if you want coat it with a little roofing cement after installing it.

Anyway I guess I need to add the dielectric step to the installation procedure.
 
#18 ·
The strength of the top mount would also be my concern, but even if it only lasts 50k miles, I think it would be worth it. I bet it will last longer than that, though.
 
#19 ·
That is were that bar pin eliminator comes in from the other thread.
http://www.insightcentral.net/forum.../modifications-technical-issues/20415-another-rear-shock-mount-possibility.html

One less part to fab and it should be more durable. I ordered a pair for $30 shipped. Between two orders I am now in for just over $60 for new rear shocks. The only part I need to fab is the bottom which appears to be the easiest as it uses the 2" nipple. If I remember correctly stock replacement shocks were over $200.
 
#20 ·
Yeah, if the bar pin eliminator works that would be excellent. It probably wouldn't be hard to fabricate your own even if the ones linked in that thread don't fit?

I have both a TIG and MIG welder, I just have no place to use them.....Can't wait to move and have a dedicated shop.
 
#24 ·
Easy solution is to add a plastic spacer like you mentioned, I'll try that when the parts come in.
 
#27 · (Edited)
Its best to use Dacro, but I don't think its available.

http://www.insightcentral.net/forum...nda-insight-forum-1st-gen-discussion/13697-no-dacro-bolts-majestic-what-do.html

Are yours broken?

If they're not then since they are now being tightened against steel instead of aluminum the coating should have no bearing. I think that the coating just serves as a dielectric between the steel bolts and aluminum mount. Again it's the dissimilar metals thing. Coatings are mentioned in the wiki piece regarding this.



AUM DACRO COATINGS
Advantages & Properties

9. RESISTANCE TO BIMETALLIC CORROSION

Excellent performances in contact with aluminum, chromium, zinc and tin; but less corrosion resistance with stainless steel, copper, nickel and lead.

http://www.aumdacro.com/html/parser/action/page/pid/108
 
#28 · (Edited)
I've been busy and wasn't following the forum enough lately. Nice work Homer! This is so much cheaper than anything else and if the results are good, that's fantastic. Not knowing about your success here, I shipped my OEM Honda shocks/struts to Pro Parts (Koni shop) today to see what they have to say.

Seems like for a lot of Insight folks, Matiz springs in the rear + the Homer 5752 mod is a great combo for very little money. I will probably see the Koni & Ground Control solutions through but there are certainly more topics start chewing on (this feels kind of like an open source project - nice!)

Handling related things I'd like to still solve:
--rear roll stiffness (not that difficult a fab project)
--rear axle pivot bushings (I'm thinking of buying some on ebay for a Golf Mk2 or Mk3 to see if they can be machined to fit)
--front caster (I may try putting a stack of washers under the rear mount & see if that does anything useful w/out damaging the front mounts/bushing)
--adjustable steering assist (I've heard you can manipulate the torque feedback signal to fool the system into assisting less (or more I suppose). No assist w/the current ratio felt very wrong to me (pull the fuse to see if you agree). I have no idea if changing the ratio is easy or not. The steering assembly is a unique part, I know that much.

With the 2nd addition to my Insight fleet (one of these days I'll post some pics/info (Eli knows) hint: it has 200hp and no turbo), I'm more interested than ever to know how to make an Insight carve the corners while sipping minimal fuel.

Joel
 
#31 ·
With the 2nd addition to my Insight fleet (one of these days I'll post some pics/info (Eli knows) hint: it has 200hp and no turbo), I'm more interested than ever to know how to make an Insight carve the corners while sipping minimal fuel.

Joel
Please tell me that this is a K-series Insight!!!:D
 
#32 ·
@Blue Civic Hybrid: yep, I bought the car from Ohio, built by a mechanical engineer from Honda N. America. It's fast but needs quite a few things to be a nice daily driver. Suspension on the car feels pretty shot (body has nearly 300k miles). Front springs are Teins from the rear of an S2000 but damping is stock and probably very tired. Since I already have 1 Monroe 5752 on hand, I'm thinking of picking up a 2nd and doing the Homer mod just to reduce the unsettled pitching behavior while I wait for something more exotic to materialize.

Has anyone with a bit more money to burn thought about trying the Homer mod on a set of these?
Koni Shocks: 52-59 Beetle, Karmann Ghia  - eShocks.com:
 
#33 ·
I'm so taking a trip up to WA when I move back to Oregon just to see the beast!!!! :D

How does it hook up? The Insight's front end is so light that even with the stock amount of power, the front end just bounces if the tires are cold....
 
#38 ·
Just finished installing and testing the Monroe shocks. There were a few issues, first of all the Bar Pin Eliminator can be made to work, but I wouldn't recommend it. The hole spacing is about 1/3" short, so they would have to be modified. They also make the shock another 1/2" longer and as is the Monroe shock have a longer extended range over the stock shocks.

I ended up using a grinder to split the top of the old stock shock and removed the stock aluminum pin. The rubber sleeve had to be ground down enough to press it into the top of the Monroe shock. I used the pipe fitting as recommended in this thread for the bottom mount.

As far as max extension, since this shock allows the read arm to extend more the springs can get loose if the rear is jacked up, other than that it works fine. The rear ride is now very firm. The stock shocks were very worn. One had no compression left and the other one had minimal compression.
 
#39 ·
Just finished installing and testing the Monroe shocks. There were a few issues, first of all the Bar Pin Eliminator can be made to work, but I wouldn't recommend it. The hole spacing is about 1/3" short, so they would have to be modified. They also make the shock another 1/2" longer and as is the Monroe shock have a longer extended range over the stock shocks.

I ended up using a grinder to split the top of the old stock shock and removed the stock aluminum pin. The rubber sleeve had to be ground down enough to press it into the top of the Monroe shock. I used the pipe fitting as recommended in this thread for the bottom mount.

As far as max extension, since this shock allows the read arm to extend more the springs can get loose if the rear is jacked up, other than that it works fine. The rear ride is now very firm. The stock shocks were very worn. One had no compression left and the other one had minimal compression.
Great write up, any pictures of the pin transplant? Any idea of what the O.D.is of the old aluminum pin so I can predrill the new shock?