Low Budget Extended Travel Coil-overs

[Kuzumonkey]

I don’t know if this has been discussed before, but I’m on the verge of upgrading my TRD Off Road suspension and after reading about everything I can find, I still can’t decide the best way to spend my money..

I like the idea, and could possibly budget, something mildly fancy but I don’t get to go off road very often. All of the challenging dirt roads and trails are closed. I’m not interested in off road parks as I can’t afford that level of modification and breakage.. When I do go off road, it’s just mild fire roads trying to find a camp site. I can’t drive fast because there is so much traffic now that I can’t do more than 25 mph without getting stuck behind a Camry, some Subaru, or a Wrangler.. Why do Wranglers drive so slow on fire roads? I thought the coil springs made those live axles ride smoother.. Topic for another thread maybe….

So what I’m thinking about is a set of 5100s up front and 5160s in the rear to handle the extra damping load of a deaver add a leaf holding all my camping crap.
At most it will be exposed to 30 to 40 mph fire roads with some potholes hit at slower but not too slow speeds. Plenty of time for cooling when I get stuck behind traffic or slow to a crawl around blind corners.

Where I’m still undecided is if I should just get 3rd gen 5100s, possibly 6112s or I’m leaning toward 2nd gen 5100s as a possible extended travel option.
I’m making quite a few assumptions here as I’m working with dimensions posted by vendors for the bilstein stuff, but the Fox numbers come from their site so I hope they’re accurate.

Baseline:

3rd gen 5100 (24-263108)
22.22” extended
17.58” compressed
4.64” travel

FOX 880-02-361 2.5 coil-over
22.59” extended
18.04” compressed
4.55” travel

3rd gen 6112
22.5” extended
17.67” collapsed
4.83” travel

Assumption: From what I’ve read, the Tacoma has about a 2:1 wheel to shock travel ratio. Bump travel is limited by the bump stop. From these shock dimensions I can guess that the bump is engaged before the shock compresses to 18.04”, so I’ll give a WAG at 18.5” shock length for bump engagement. Just for comparison purposes.

For example: 3rd gen 5100 extended 22.2 minus 18.5 equals 3.7 available compression or 7.4 inches of actual wheel travel.

Due to bump stop we have very similar travel across all three shocks at 8.18" for the fox and 8" for the 6112.

Again, this is with the guess of when the bump engages, so not actual known travel, just for comparison.

Comparison:

FOX 883-02-025 (extended travel) 2.5 coil-over
22.93” extended
18.04” compressed
4.89” travel

Extended 22.93 minus 18.5 bump engagement is 4.43 allowing 8.86 inches of actual wheel travel.

So if I’m close to correct, the extended travel with FOX may be less than an inch.

This is where it gets interesting for me.

2nd gen 5100 (24-239370)
22.56” extended
17.03” compressed
5.53” travel

2nd gen 5100 extended minus 18.5 estimated bump stop gives 4.06 available compression or 8.12 inches of actual wheel travel..
Already more than the 3rd gen 5100..

And here is where I go off the rails.

What if we had a 0.5” spacer above the top hat of the 2nd gen 5100.
This would change our dimensions to:

23.06” extended length
17.53” compressed (still safely under the FOX and 6112 compressed lengths)
5.53” travel (no change of course, but more is usable below the bump stop)

New 23.06 extended minus the guessed 18.5” bump stop yields 4.56 available compression or 9.12 inches of actual wheel travel..
If I’ve overestimated the bump stop length, then it could be even more travel.

I’m guessing we might need aftermarket upper control arms to make this work, but the savings in shock price could accommodate that cost.

I don’t want more than one inch of lift, so if I do this I would leave the snap ring at its lowest setting, and I don’t plan to go bigger than 265/75 r16s so alignment and caster shouldn’t be an issue. I’ve read that the TRD Pro has an extra inch of travel, so if that’s true I might not even need the control arms.

What do you think?

 

[TCOTUE]

I recommend giving this channel a watch on YouTube. Tons of information.

IFS Info Series (YouTube)

I stubbled across this guys page. Tons of info I didn’t know about. He also does a extremely in-depth review of Dirt King vs Camburg long travel kits. Seriously impressed with his info. Give it a watch. https://youtube.com/c/TinkerersAdventure

tacoma3g.com

 

[Kuzumonkey]

Thanks. I had seen his videos pop up before but hadn't watched them.. He's very thorough, and it looks like this probably would work for a low cost extended travel option. If what he notes on the FJC is really similar to the Tacoma, might want to consider a thinner top spacer. It's really close, so I guess I would want to check measurements before installing... This is assuming the 2nd gen 5100 specs are accurate. Would be nice to confirm those before buying.

 

[Kuzumonkey]

I ordered my stuff and installed it.

The short version is, putting 2nd Gen 5100s on a 3rd Gen Tacoma will extend the travel.
If you put the clip on the second notch you get about an inch of lift with no extra preload on the spring.

The longer version:

Removing the springs from the stock shocks is a bitch without fancy spring compressing tools.
I had to go buy and rent more manual compressors and it was not a comfortable experience.
Due to the extra time all of that took, I was neither in the mood nor had the time to do all the testing and documenting I originally wanted to do, so no pics and not a lot of measurements from this.

Essentially I stuck the shocks back in place without the springs and compressed the suspension with a jack until the control arm hit the bump stop and just started to move the truck.

I marked the center of the hub with a silver paint pen by rotating the hub and holding the pen.
I used a yard stick with zip ties to note where the hub started in relation to the garage floor and then stopped at the bump stop.

Points where there could easily be errors:
• Maybe I didn’t hit the center of the hub perfectly, so fractions of an inch there.
• I expect inconsistencies in how tight the strut mount was in compressing the rubber bushing affecting extension lengths, so fractions of an inch there.
• Could be differences in bump stop compression, but I got/used the same marked point for both so I feel pretty good about that one.

Results:

OEM shocks measured travel - 5 and 7/8ths inches of travel

2nd Gen 5100s measured travel – 8 and 11/16ths inches of travel

I expect both actual travel numbers to be a bit larger as the bump stop should compress more under the weight of the truck.
However, this is also measured with the sway bar disconnected so that could limit the used travel.

I had planned to try and put a half inch top spacer on top of the 5100 to further increase usable shock travel.
I found that I could not get the 5100 to fit with spacer and feel comfortable with it. The lower control arm didn’t want to move without loosening the bushings and the inner CV joint was being pulled out farther than I liked. I was also concerned with brake line and speed sensor cable lengths.

I used rubber 0-rings on the shock shafts to see how much of the shock travel was used and the 5100 was near its bottom out without the spacer. I think there was enough travel left but the shock has a hard bottom out and I don’t know how much the bump stop can compress. It just didn’t seem worth the risk since I already had good travel gains that matched what my rear add-a-leaf and 5160s gave me.

Based on where the o-ring was on the OEM shock and the shorter overall length, I think you could easily put a spacer on top of that shock and get an increase in travel with minimal risk… But do this at your own peril... I didn’t put any effort into confirming that.

Another point I found interesting was how much the stock springs are compressed on the OME shocks.
I compressed the spring to the point it just barely allowed the shock to wiggle. The bare minimum required to remove the OEM shock. It was not a comfortable experience.
On the 5100 it matched up to the second notch from the bottom with almost a ¼ inch to spare. There was no additional spring compression at that setting vs OEM.

I wasn’t concerned about lift, so I didn’t really measure for it, but it appears to have given me about 1 inch in the front. Compared to the almost 2 inches that the rear add-a-leaf gave, the truck still seems balanced to me with about an inch and a half of rake.

One last point that might prove useful:
I put a little bit of anti-seize on the snap ring when I assembled the shock. I thought it might be helpful later if I decided to change settings. I found it was immediately helpful with rotating the lower mount to align with the top if you are a little off when putting the spring back on. I was able to put a screwdriver in the lower mount and rotate it easily with the top installed.

As far as the ride is concerned:
There are plenty of reviews out there on this so I won’t go into detail, but my impression is there is a little more harshness and little less brake dive, but you will probably be the only one who can tell.
It’s subtle, but different.
It will improve off road rough handling allowing faster speeds with a decrease in small bump smoothness. I would advise floating the washboard sections with a bit more momentum to take advantage of the change in how the truck rides.