Shocks & springs from 2017 5th Gen into 2008 4th Gen v6. Perfectly compatible?

[Seymore Butts]

I have a buddy who just bought a '17 4R (unknown engine and trim level) and he immediately upgraded shocks and springs. I can have his OEM shocks and springs for close to nothing.

His "parts guy" says these shocks and springs should be a perfect drop-in into my 2008 4R SR5 v6.

Now, I know for a fact that 4th Gen and 5th Gen OEM shocks/springs have different part numbers, so I'm not as sure as the "parts guy" appears to be.

Besides, I don't have any reason to believe that these two trucks have the same or close-enough front/rear weight distribution resulting in the same suspension specs.

What do you think? Perfect fit and spec, or should I avoid this potentially dangerous experiment?

 

[KaseyMcc]

I have a buddy who just bought a '17 4R (unknown engine and trim level) and he immediately upgraded shocks and springs. I can have his OEM shocks and springs for close to nothing.

His "parts guy" says these shocks and springs should be a perfect drop-in into my 2008 4R SR5 v6.

Now, I know for a fact that 4th Gen and 5th Gen OEM shocks/springs have different part numbers, so I'm not as sure as the "parts guy" appears to be.

Besides, I don't have any reason to believe that these two trucks have the same or close-enough front/rear weight distribution resulting in the same suspension specs.

What do you think? Perfect fit and spec, or should I avoid this potentially dangerous experiment?

I just did a 5th gen to 4th gen swap a few weeks ago. You'll have to do a few minor modifications, but they will work. On the front, you'll just need to either grind down the lower bushing (think where the bolt goes through to mount to the LCA) on the strut, or slightly pry out the tabs on the LCA itself so the slightly bigger bushings will fit inside, then just tighten down the bolts and the tabs will suck back in against the bushing.
On the rear, the coils swap out just fine, but the little bumper bushing thing that go between the shock itself and the frame are just slightly bigger than the 4th gen, so you'll need to ream out the hole in the frame for it to fit up in there like it should.
Other than the minor tweaks, the 5th gen suspension bolts right in to a 4th gen.

 

[Seymore Butts]

Thank you, Kacey!

Do you happen to know if the specs are compatible? In terms of compression force, available travel range, and whatever technical terms are used to describe shock and spring performance.

 

[KaseyMcc]

Thank you, Kacey!

Do you happen to know if the specs are compatible? In terms of compression force, available travel range, and whatever technical terms are used to describe shock and spring performance.

I don't know the technical specs, but I seem to remember reading the 5th gen suspension is the same that goes on the FJ cruiser--but I don't remember which thread I read that in. I wouldn't get too caught up in worrying about matching the specs unless you're that anal. Despite being a V6, depending on the configuration the 5th gen can weigh up to 400lbs more than the V8 4WD. I wouldn't overthink it too much. You'll get a slight lift, but don't expect much. I noticed a definite improved stance, but it still has that forward rake. Despite the different part numbers and slight differences, I wouldn't consider the 5th gen suspension to be any different from the 4th gen in terms of ride characteristics or technical specs. Just bear in mind that in the future you'll have to replace the rear shocks with 5th gen since you've modified the frame mount. The front you can go right back to the 4th gen if you want; likewise for rear coils. Be sure to ask your friend which front strut came from driver side/pass side, or look for different paint on the coils...I bought from a dealership that said they were the same, just curious if that's really the case because it seems weird to me.