OP
Dave Kishpaugh's (Jeep West) Geometry Correction Bracket Measurements
- Thread starter 01TJ-Blues
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Are you on the throttle and spinning the tires when it starts to hop or are you trying to crawl? Also is it on steep hills, hills, level, etc....
Wheel hop in a traction rich environment when crawling a steep hill and wheel hop due to spinning tires in snow may be a little different beast. I will have to think about it, and maybe others can comment. Either way the hop comes from loss of traction followed by gain of traction and most likely load and unload of components thus the lower you can get the AS the better.
OP
With snow it is indeed a different creature, much like deeper sand I would think. You generally get the hops when you are on the more packed in snow on more flat terrain. There aren't may times in snow it gets as steep as the rocks and when it is steep you just get spin without hops. The only way I can describe snow hops is that you "move" the traction from under you and it drops...basically the packed snow gets spun out form under you, the tire drops to the softer snow which has a ledge on the leading edge of the tire and repeat. Usually this happens when crawling through the snow, if you spin it up hard it will just spin and either gain forward momentum or bury you in your own hole. Or if you have momentum you can keep the spin-push going and only until it starts to slow and dig do the hops come back in. We are usually aired down to 4-10 psi so that's about as good as you'll get for a footprint too so again, my mystical chase for snow traction could be for no reason, it may not exist. I'm leaning towards a geometry issue because we have a couple of IFS and leaf spring Toyotas on 33-35" tires that go with us and they float through the snow pretty easily, similarly a fellow TJ has a long arm setup that doesn't get the hops but 3 of us on short arms seem to be the only ones that fall victim to it.
I do get out in the dry months too and as all others have described its the ledges that really get the hops, again like snow when you flick out the traction snow and drop to the soft snow butted up to a small ledge of snow in front of the tire.
Just thinking while I am typing; Anti-Geometry (squat and dive) are a result of forces induced by the drivetrain. If you have high anti-squat due to the short arm lift and you get a loss of traction followed by a gain of traction, the control arms are going to lift the rear end of the vehicle until it loses traction and drops the body, thus causing the hop (this would apply in dry or snow). So I would think that a geometry correction (not saying how to correct it) would reduce the hop. Is there a way to prevent the loss of traction? Are the Tacos and the long arm also slowly spinning, gaining traction, spinning....... like you state above and just not hopping or is it just the short arms?
Off topic, when I was a kid I had a '78 chevy blazer (stock) and my buddy had a '79 Ford Bronco (may have had a little lift, but can't remember if it was body, SOA, etc.... to long ago). We used to do a bunch of snow wheeling and my Blazer never really had a wheel hop problem, but that Bronco would hop like crazy. Back then it was a Ford vs Chevy debate and we didn't know anything about axle wrap, etc.... Spent a few nights out in the woods with a come-along trying to get both Ford and Chevy home!!
Unfortunately, that blazer didn't make it too long, it was a rust bucket when I got it and it eventually became a safety issue and I didn't have the funds to fix so I sold it to a guy who was just wanting the drivetrain.
Unfortunately, that blazer didn't make it too long, it was a rust bucket when I got it and it eventually became a safety issue and I didn't have the funds to fix so I sold it to a guy who was just wanting the drivetrain.
OP
I agree with all you stated above and am aligned in your thinking. The Toy and the LA TJ are also moving at roughly the same speed, weights and loads are close to the same and there is a mix of transmissions, so that doesn't drill down the issue for us either. The only way to prevent loss of traction would be to increase tire size and/or width for a larger footprint from what I've seen but the Toys are both on 33s and 35s and don't hop. They go and go until they spin and dig but they do not start the hopping. Now for them it could be the leaf springs are less liking to hop and ratchet or possibly they are stiff sprung and have more overhang off the rear.
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OP
The Bronc would have had IFS (ish) front but other than that the two described rigs should have been a close match for sure. Fun reminiscing, I had an 85 Toyota SR5 truck on 33s...I don't know if I could have pushed that thing any harder than I did as a kid and it was a snow wheeling weapon...leaf springs front and rear.
I've seen it where I strongly suspect the difference is auto vs manual, where the manual isn't geared low enough to not break traction.
OP
Two of us have autos and one with a manual. All 3 do it but the manual is definitely working the clutch in slow situations to prevent it, until he clicks to 4-low then he gets the same result. Most of the stuff is a 1st gear-4 high situation.
OP
Here is an observation that is pretty cool...or not. on of our other guys is running BFG KO2s, he rarely hops and he can usually push past where we with mud terrains to quite easily. He has a non adjustable CA 4" lift with none of the heavier mods the rest of us do and although he struggles in the summer more gnarly stuff in the winter he rallies around like a champ.
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I’ve seen the same between my dad and I on very steep waterfalls you have to crawl up. There’s one in particular I can walk right up every time and stay “glued” to the wall. He just can’t get traction on it. Slips and hops like crazy with same tires. I even got out and tried to do it in his rig and couldn’t. The difference there I suspect is the manual vs auto and staying at the limit of adhesion. I couldn’t make the tires spin slow enough in his rig.
Since installing my doubler I don’t see the hops I once did. I have much better control of my wheel speed. The tires are still trying to crawl under the rig, but it happens at a much slower pace so I don’t see the hops.
Very low gears are a must with a manual in my opinion.
All the more reason I want to change to an auto.
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@01TJ-Blues, one thing I noticed when on snow runs in the PNW was rigs with front and rear tires that would spin ever so slightly out of sync, would have a much higher tendency to start hopping than "tighter" drive trains. Not saying that if that is your issue or not but it is a factor. I have also seen Jeeps with completely stock suspensions hop in the snow just from having their tire pressures not quite right. A couple pounds is all the difference it would take to stop the stock Jeep from hopping.
Brianj5600
TJ Expert
Brianj5600
TJ Expert
Not currently but I saw the same thing before I did geo correction as well. We are putting an auto in his rig soon so we will see if that makes the difference!
OP
I'm in Idaho so we definitely are playing with close to the same environments and we have absolutely expired tire pressure as the solution. Mine will do it fully unlocked as well as fully locked so it isn't one or two wheels spinning at different rates because locking it up would stop that potential issue. And again, the long arm and the Toyotas don't have the issue, only the short arms in our group. I also highly doubt all 3 short arm TJs have "looser" drivetrains than all the other rigs, much more likely the geometry being different is the issue.
Well, it was a possible avenue, at least you ruled it out.
I know where Orofino is, smack dab in the middle of the woods
and yes the snow there is very similar to the "Wet" Coast mountains. Beautiful country up there too!!