Rear suspension

Well... I already spent too much time on this exact same problem. When it comes to matching up springs and shocks the way they do in performance cars, the process doesn't translate so well to an economy car. For one, the price point is ridiculous.

However, there are people in the business that know the parts system well enough to get a identical mounting, or at least a mount that can be re-welded for your car, but with slightly stiffer springs that will fit. Of course it may harm cars handling at freeway speed. Won't know until you try I guess... As in I spent so much time thinking about all the factors and got discouraged. But hopefully others will come along with some thoughts that are more encouraging?

 

225k..? have you ever replaced the struts/springs? Iv hauled and towed a lot with mine(191k) and just this year replace all 4.. so much better..

Literally felt like a brand new car, except for all the rattles n squeaks and the crack in dash vent.

 

I don't think there are many options for the Prius.. When I was looking to replace my struts the more expensive stuff looked exactly the same as the cheaper stuff..

 

I used lift helper springs for $12 at autozone.
Easy to install and cheap good mod for extra weight in the Prius.

SM-J737T1 ?

 

If you have inspections this isn't a good option. At least it wouldn't go through yearly inspection here.

It will also cause uneven and more force on the spring. That will make it more likely to have a spring failure in the future. Which is why it won't go through the inspection.

 

Well I choose this mod because it works and it's cheap. Honestly I just drove 3000 mile camping trip with fully loaded thule box roof rack, trunk and back seat for winter camping trip.
I have towed bikes, gear and trailers for many years and hauling heavy loads in cars and trucks you come to realize in all case the safety and stability in any vehicle comes with correct height of the rear springs needs to be adjust properly when adding weight and towing.
So knowing in advance I was going to haul lots of gear I installed helper lift spring made the world of difference. Honestly an hour of work and $12 for parts has made my Prius safer on the road, I would highly recommend this mod for all Prius drivers who haul any heavy load like 4 people in the car. That's why fully loaded and at 103mph the car was very stable and predictable. No floating or bouncing just very firm and controlled.
Obviously this mod can only be done countries that allow it of course.
If you wanted to replace it with heavy spring I read Toyota Matrix rear spring are better for extra weight.

Second photo shows my car without the helper lift spring mod with 10x case of water in the trunk and back seat.

The top photo shows fully loaded with camping gear and 2 people. No compressed springs.



SM-J737T1 ?
View attachment 184963 View attachment 184964

 

Yes. I'm not saying that it wouldn't work. Or that springs would fail, it's just more likely for them to fail than without the mod.

 

I think that I saw a thread on here about using springs (and perhaps struts) from a 4WD vibe. Seemed like a pretty solid set-up as the vibe springs appear much more heavy duty.

I have been looking at doing the same type of beef-up of rear suspension. As I intend to install a trailer hitch and tow ocassionally.

 

Do you know where that thread is? I've not seen it yet, but would like to see it.

 

I am on the road right now. When I get home tonight I will look for the AWD Vibe thread. In the meantime I have ordered the RR strut assembly ( fully loaded) from Advance Auto for: i. Gen2 Prius, and ii. 2009-10 AWD Pontiac Vibe. Expect lots of pics, comparisons and measurements of the two setups.

 

Awesome... Thanks... Looking forward to this!!!

 

Link to Vibe/Matrix Spring thread: Heavy Springs And Lift Upgrade | PriusChat

Next Tuesday 01212020 (M is a holiday), I should be receiving the fully loaded RR strut assemblies from Advance Auto for: i. Gen2 Prius, and ii. 2009-10 AWD Pontiac Vibe. Expect lots of pics, comparisons and measurements of the two setups. My intention is to swap the whole Vibe AWD strut assembly into my Gen2. But only after I make sure all the particulars are the same except for spring rate and spring thickness.

Alternatively, if there are substantial differences then I will likely just use the AWD Vibe springs on new Gen2 rear struts with the spring perch modification described in the link above (or perhaps use the Vibe springs on new Vibe rear struts with Prius bearing mounts at the top of the strut -we shall see).

 

Vibe AWD RR strut and Prius Gen2 RR struts came in a little sooner than expected. Vibe top bearing assembly looks like it would bolt in BUT the Vibe strut assembly appears to not have enough travel and be the wrong overall length. Take a look and let me know your thoughts.

Monroe 172394R Complete Strut Assembly for 2006 Prius RR

Compressed Length: 12.560in.
Travel: 6.260 in
See: Advance Auto Parts - Down for Maintenance
My measurement from bearing surface top to center of bottom eye: about 16 1/4"


Monroe 172600R Complete Strut Assembly for 2009 Pontiac Vibe AWD

Compressed Length: 11.452 in
Travel: 2.422 in
See: Advance Auto Parts - Down for Maintenance

My measurement from bearing surface top to center of bottom eye: about 13".

IOW, the Prius strut assembly is about 3 1/2" LONGER than the 2009 AWD Vibe RR strut assembly with about four ("4") additional inches of travel.

PS Last picture has full picture of both strut assemblies. Near the top of each strut assembly is a piece of blue tape with the Monroe part numbers on them.


Pics set forth below:

 

So this mod isn't going to work?

SM-J737T1 ?

 

This is not a bolt-in alternative. However, you could try either of the following:

1. use AWD Vibe spring on a stock* 2nd gen Prius strut and bearing cap; or

2. Buy, or fabricate, strut extender to make up for the 3 1/4" shorter length when using the Vibe AWD strut assembly.

See (similar shock extender for Jeep Wrangler - concept only): 2007-2017 Wrangler JK Front Shock Extender Kit For 2-4" Leveling Kit | eBay

*- other Priuschat thread describes moving Vibe spring perch to Prius strut. See: Heavy Springs And Lift Upgrade | PriusChat

 

That other thread is mine. I have a few thousand miles on the new struts. The car rides better with a heavy load than it does empty. My friend drove his car from MN to Mexico with just the heavy rear springs. He says the car handles better loaded than it ever has. Next I'm going to try lowering tire air pressure to 32 psi for when the car is empty.

You bought a few more parts than needed. To make this work take the springs and bottom spring perch from the Matrix 4WD struts and install them on the Prius struts.

 

I purchased the two fully loaded struts (namely, for 2009 AWD Vibe RR and 2006 Prius RR) as a comparison of the two strut assemblies. My hope was to bolt in the 2009 AWD Vibe assembly. 2009 AWD RR strut assembly will not work because it is about 3 1/4" shorter and has about 4" less travel.

Both strut assemblies have been returned to the auto parts store for full refund. Now, I am on the hunt for a pair of rear strut assemblies from 2009-2010 AWD Vibe. With the idea of emulating your build by: i.) reusing AWD Vibe springs; and ii.) reusing AWD Vibe spring perches.

IOW, still working on this project.