Front End Movement

[Tiger98]

I'm having an issue where when the clutch isn't engaged, slowing down by letting off the gas or speeding up will initially cause the jeep to lurch forwards or backwards like the frame is catching up to the front axle's movement and they aren't tight and in sync. At least that's what a mechanic I took it to thought the problem might be. I tried switching out the upper front control arms since the lowers looked fine so that the axle wouldn't move any but that didn't get rid of the problem.

It's at its worst when driving at a slow speed like in first gear especially. It can be very jerky if the clutch isn't at least partially engaged and I have to press the gas pedal gently. I know it's geared very low and I've learned to be slow and steady with it and utilize the clutch at low speeds to avoid getting thrown around. It just feels like the front axle is moving separately. I can't seem to find much if anything about this problem online so I figured I would try asking here if anyone knows what could be causing this.

 

[macleanflood]

Pictures? Especially if your front track bar?

-Mac

 

[JMT]

I don’t think you have a problem. Lurching is pretty common for a MT geared deep.

 

[jjvw]

.... I know it's geared very low ...

What are the axles geared to?

Tell us about the shocks and sway bars.

 

[Tiger98]

Thanks for the responses! I'll get some pictures as soon as I'm able to.

I was wondering if it might just be because of the insane gearing but the loose feeling of the front end made me question that as well as the mechanic not being able to align the front end and keep it there because he said it would move on him.

I just put on new Rough Country shocks in August and new sway bar end links last week because the old ones had a ton of movement. I'll have to check again what the axle gearing is, it's faded and hard to read and I couldn't match it to any of the usual ratios though it was close. I believe it was in the mid to high 4s.

Basically the lurching only happens at low rpms. Whether letting off the gas pedal at regular driving speed or barely depressing it and keeping it at constant pressure at very low speed without the clutch.

 

[Tiger98]

Here are some photos of the front end

 

[jjvw]

Thanks for the responses! I'll get some pictures as soon as I'm able to.

I was wondering if it might just be because of the insane gearing ...

We need to know more about this insane gearing.

 

[Tiger98]

We need to know more about this insane

I don't know if you'll be able to make anything out by this, but it's all I have to go off of. It could be the low gearing causing the lurching like JMT said, because when I'm engaging the clutch it never happens.

I just thought there might be something going on due to the mechanic not being able to keep the front aligned and when I'm making a really sharp turn at low speed as in a parking lot I can hear a knocking noise and it feels like it's binding up and jerky. Only happens when I turn the wheel pretty far though and not during regular driving.

 

[jjvw]

I don't know if you'll be able to make anything out by this, but it's all I have to go off of. It could be the low gearing causing the lurching like JMT said, because when I'm engaging the clutch it never happens.

I just thought there might be something going on due to the mechanic not being able to keep the front aligned and when I'm making a really sharp turn at low speed as in a parking lot I can hear a knocking noise and it feels like it's binding up and jerky. Only happens when I turn the wheel pretty far though and not during regular driving.

View attachment 487171

Your gearing isn't insane, nor is it the cause of whatever you are experiencing. This is most likely a shock or a sway bar issue allowing the body to react dramatically to engine torque.

 

[Rickyd]

I just thought there might be something going on due to the mechanic not being able to keep the front aligned

describe the part that won't stay aligned?

The toe in?(your stock tie rod will bend easily)

Camber?(worn ball joints or wheel bearings)

Caster?(worn suspension links)

when I'm making a really sharp turn at low speed as in a parking lot I can hear a knocking noise and it feels like it's binding up and jerky.

from the front or the rear?(You could have binding axleshaft ujoints or other loose parts in the front.)

An autolocker in the rear could do this too.or when left in 4x4

 

[Tiger98]

describe the part that won't stay aligned?

The toe in?(your stock tie rod will bend easily)

Camber?(worn ball joints or wheel bearings)

Caster?(worn suspension links)

from the front or the rear?(You could have binding axleshaft ujoints or other loose parts in the front.)

An autolocker in the rear could do this too.or when left

The mechanic couldn't identify what was causing the front end to move and keep him from aligning it but seemed to think it was control arm bushings. I checked the lowers and they were fine. The uppers were bad and the arms were old and stock so I put new ones on.

The mechanic told me he got the toe in and the thrust set properly

I had a different shop check the ball joints and they said they were fine

The sway bar end links? I just replaced those, so they should be good

The knocking and binding comes from the front and seems like it's by the tire so it could be the u joints, yeah. Do they need adjusted or is that something that typically needs replacement?