Effect of Extended/Lengthened Steering Knuckles?

I'm currently looking into every option (short of RCLT) to strengthen the steering on my 07. I'm going to be installing 37s in the next couple of weeks. One of the main mods I'm investigating is lengthening the steering knuckles on the spindles by about 50%. Marlin Crawler did this on the RCLT, with the theory being that the additional leverage would reduce pressure on other steering components. My plan is to cut the end of the knuckle off of a new set of spindles (where the tie rod attaches). I'll add a piece of alloy steel (haven't decided which yet) to lengthen the knuckle, and then TIG weld everything back together. This will utilize stock outer tie rod ends, and I'm planning to sleeve the inner rod end to strengthen it. I don't do any wheeling just for the sake of wheeling; only hunting. Most of the more difficult terrain will be in deep snow, no rock crawling. I'm hoping this system will hold up without having to replace the steering rack.
My main question is if there will be any unintended effects from lengthening the steering knuckle. I'm worried about 1. How fast it will steer 2. Steering sensitivity 3. Effect on turning radius. There's plenty of room for the extended knuckle, and the welding/fab/design work won't be an issue for me. Does anyone have any experience doing something similar?

 

Are you wanting to lengthen to lift the truck?

 

Yes you will have more sensitive steering and more steering angle per wheel degree, "faster steering". A buddy extended his steering tabs on his knuckles on his drift car for more turn in and drift angle control.

Personally if you're just doing light trails and service roads to access hunting spots I don't think you need this.

I would however gusset the spindles though with all that 37's weight.

 

Not needed, just throw some Drt Fab spindle gussets on and forget about it. I have 50k miles on my truck of hard wheeling/crawling/some whoop bashing, and am just now getting some play on my inner tie rods. Everything else has held up great.

 

Going to chime in here. I would advise against lengthening your steering arm. A number of problems can result from this (incorrect Ackerman, steering angles and bump steer to name a few) my gusset kit strengthens this section plenty. The intention behind my gusset kits is a cheaper alternative to a fully fabricated spindle. Stock components will hold up to what you’re planning on doing for the most part. I also make a cab mount relocation kit to fit 35s. Could you give some more info to your set up?

 

It would be the opposite wouldn't it? If Im understanding correctly OP wants to move the outer tie rod location further away (further forward on the truck) from the axis of rotation of the spindle..? Greater moment arm there would mean less steering angle for a given steering wheel input (and lower sensitivity) wouldn't it?

 

You will end up with less steering angle for each inch of rack stroke this way, so it will increase turning radius.

 

You're probably right in this instance I may have misunderstood what he was meaning and obviously the Tacoma's steering geometry is going to be different from a pro-am drift car.

 

Ford puts a different upgraded steering knuckle on the F-150 Tremor vs the regular F-150 I don't know if the knuckle is a longer one. I wonder what the advantages are? The Tremor only sits an inch higher if I recall correctly.

I would think a longer knuckle on any lifted application would be a plus, but I don't know one way or the other.

 

DRT, I didn't see the double shear kit on your site, but I like how your spindle gusset runs out onto the steering knuckle!
The truck is currently on 285/75R17 (~34.2x11.2) with stock 4 Runner wheels and 1.5" spacers. Stock UCA/LCA and the old style Toytec coilovers set at 2" of lift. The plan is to keep the investment into the truck as low as possible. It will end up with UCAs, reinforced stock LCA, and Fox 2.5 extended travel coilovers sometime this summer or next.
Most of the abuse it sees is all in the snow, during cougar and bobcat hunting season. The truck is frame deep in snow almost weekly (and sometimes daily) from December-May. Occasionally I end up somewhere rough in the desert, but I don't do any purposeful rock crawling.
Regarding the tie rods, I did a bit more research (mostly on drift car sites). Lengthening the knuckles would make it steer more slowly and reduce feedback. It could potentially result in a larger turning radius, depending on how much travel the rack has. Some solve that issue with tie rod extensions, but that could cause bump steer. There is also a possibly of messing up the Ackerman angle, which would increase tire wear.
All things considered, I'm going to leave them stock length for now. I'll probably still end up doing a new set of spindles when I'm ready to do gussets and bearings.