Bilstein TRD Baja vs Pro Suspension Comparison + Toytec Spacer

I've never seen this info posted anywhere so figured I'd get a post up for posterity sake. I happened to have both the Pro and Baja suspension and I've always wondered what the differences were. Yes, we know the valving is different, and yes we know the spring rates are different... But, in order for both setups to yield the exact same ride height there had to be more of a difference than just spring rate. (Technically, if the only difference was rate then ride height would also differ.) So here's what I found...

First, springs. Not surprisingly, the springs were identical in length, at 14".
Pro (600lb) on the left. Baja (650lb) on the right.
They appear to be identical but obviously it's understood they have different spring rates.



Next up, the shocks. Overall length, and overall design look identical at first glance. They seem to physically be based on the same basic shock body and design - modeled after the 6112 Bilstein as we all know. So, no real surprises there.





So, what's the difference? Turns out there's a, not insignificant, difference in circlip location. As you can see, there's a 0.7" / 18mm difference in the location of the grooves for the circlips.

The Pro shocks (with lower spring rate) have the grooves higher up than the Baja shocks (higher spring rate). This makes sense as the Toyota engineers essentially increased the preload on the Pro in order to create the same amount of lift as the Baja despite the lower spring rate. That said, this was more of a difference than I was expecting. (I imagine if you do the math then it probably checks out.)

Baja on the left, Pro on the right.


Pro on the top, Baja on the bottom:



And since I had them on hand I figured I'd provide some measurements on the factory spring perch vs the Toytec 1" Baja spacer. The Toytec spacer is 0.5" thicker than the stock spring perch. 0.5" of added preload is how they give the 1" of lift.

Stock spring perch:



Toytec 1" Baja Spacer:



This suspension is pretty old by now but hopefully someone out there will find this info useful.

 

Awesome post, we never got the tx or pro in canada 2nd gen, so this is awesome to read up on.

Have you driven on both? I imagine the TX is more firm, albeit very similar.

 

Unfortunately, I have not. I bought these Baja coilovers purely because they had a Toytec spacer and they were cheaper than buying the spacer new. And the Baja shocks had higher miles and looks like maybe one was leaking so I imagine they're past their prime.

Other reviews out there confirm that the Baja is a bit stiffer than the Pro. One thread I saw also said one was digressive and the other was progressive valving but I can't confirm that and the thread I read made it seem like this info had not been confirmed. If anyone has solid info on that please post it.

I had been running the Pro coilovers + 3/8" thick top hat spacer. Figured I would install the Toytec preload spacer and remove the top hat spacer. But, I also considered swapping the springs as well or instead. But once taking these measurements it seems that swapping springs wasn't ideal for me. It would have added ~0.75" of preload vs the 0.5" preload from the Toytec spacer. I opted for the more conservative option