Motor Mount Height Question

Hasselblad · 2026-09-15T10:21:06-0600

So when I did my body lift, I added spacers to the motor mounts to lift it accordingly. Fast forward to the belly lift I just did. My pinion angle (DC shaft) has been adjusted for the new angle, but getting vibes (mostly accelerating at 30MPH and noticeable at speeds beyond.) and since the belly lift brought the angle of the motor back down nose-wise I am wondering if I may need to add more of a MML to regain the angle of motor/trans/TC that I had before the belly up. The Tereflex skid came with spacers and I am wondering if it is feasible to stack spacers by adding them to the existing ones (JKS)

Does the 1.25 Body Lift + Belly Lift require higher motor mounts, or am I overthinking this? Over next weekend I will be peeking at u joints to rule those out as well.

For data sake, adding the new skid brought the nose down to the point the fan was hitting the shroud, so I dropped the shroud slightly.

Chris · 2026-09-15T10:23:43-0600

You're overthinking it considerably. If you have vibrations, just adjust the driveshaft accordingly until they go away. Simple as that

Hasselblad · 2026-09-15T10:34:25-0600

Chris said:
You're overthinking it considerably. If you have vibrations, just adjust the driveshaft accordingly until they go away. Simple as that

Well I dialed the UCAs to the least vibes, which has the pinion angles equaled out, and thought it would be a bad idea to go beyond that, so suspecting it is not an angle issue of the pinion.

Chris · 2026-09-15T10:37:09-0600

Hasselblad said:
Well I dialed the UCAs to the least vibes, which has the pinion angles equaled out, and thought it would be a bad idea to go beyond that, so suspecting it is not an angle issue of the pinion.

What you could be experiencing may not be vibrations from the driveline at all. It could be vibrations from the transfer case hitting the tub or the belly pan itself and creating resonance like vibrations and certain RPMs. That shouldn’t have anything to do with the height of the mounts though.

macleanflood · 2026-09-15T10:37:18-0600

Thread 'How to align your Jeep Wrangler TJ'

Oct 31, 2015

Here's how to check and adjust your own toe-in that also includes how to center the steering wheel as well as re-center the axle if necessary. With just a little care on your part with nothing more than a tape measure, a big set of pliers, and a wrench, you can easily set your toe-in with as much accuracy as an alignment shop can. Really.

Start after making sure the front axle is properly centered. That may involve adjusting the trackbar's length which can only be done if there's an aftermarket adjustable-length track bar installed. Or if the original OEM track bar is still installed and...

jjvw · 2026-09-15T10:38:32-0600

Hasselblad said:
So when I did my body lift, I added spacers to the motor mounts to lift it accordingly. Fast forward to the belly lift I just did. My pinion angle (DC shaft) has been adjusted for the new angle, but getting vibes (mostly accelerating at 30MPH and noticeable at speeds beyond.) and since the belly lift brought the angle of the motor back down nose-wise I am wondering if I may need to add more of a MML to regain the angle of motor/trans/TC that I had before the belly up. The Tereflex skid came with spacers and I am wondering if it is feasible to stack spacers by adding them to the existing ones (JKS)

Does the 1.25 Body Lift + Belly Lift require higher motor mounts, or am I overthinking this? Over next weekend I will be peeking at u joints to rule those out as well.

For data sake, adding the new skid brought the nose down to the point the fan was hitting the shroud, so I dropped the shroud slightly.

If the belly skid lifted the transmission mount, then it would make sense that the engine should also be lifted to flatten out the rear output.

Hasselblad · 2026-09-15T10:47:48-0600

macleanflood said:
View attachment 710294

Thread 'How to align your Jeep Wrangler TJ'

Oct 31, 2015

Here's how to check and adjust your own toe-in that also includes how to center the steering wheel as well as re-center the axle if necessary. With just a little care on your part with nothing more than a tape measure, a big set of pliers, and a wrench, you can easily set your toe-in with as much accuracy as an alignment shop can. Really.

Start after making sure the front axle is properly centered. That may involve adjusting the trackbar's length which can only be done if there's an aftermarket adjustable-length track bar installed. Or if the original OEM track bar is still installed and...

Jerry Bransford

alignment lj alignment tj alignment

Replies: 400

Forum: TJ How-to Guides

Yup, Pinion is correct for double cardon.

Hasselblad · 2026-09-15T10:49:43-0600

jjvw said:
If the belly skid lifted the transmission mount, then it would make sense that the engine should also be lifted to flatten out the rear output.

That was my initial thought as well. The lifting of the tran mount caused the motor to pivot forward and down, and making the driveline angle that much more extreme compared to the pinion.

macleanflood · 2026-09-15T10:55:08-0600

Pictures and brands used might help.

-Mac

Hasselblad · 2026-09-15T11:23:22-0600

Tereflex Belly Up Skid
Tom's Double Cardon Shaft (rubi version)
JKS Motor Mount Spacers
Metalcloak double adjust UCAs
Meany-Pants WTJF.com guy's body lift (you can figure that out no doubt)
OME Springs, Rancho Shocks

Let me know of what specifically you'd like a pic of

Hasselblad · 2026-09-15T12:07:37-0600

macleanflood · 2026-09-15T13:21:23-0600

Pinion angle looks high in the picture...but that could be the angle of the shot...

-Mac

Hasselblad · 2026-09-15T15:27:16-0600

macleanflood said:
Pinion angle looks high in the picture...but that could be the angle of the shot...

It's currently at 0 degrees. Double/triple checked with digital gauges. Went off the flat back of the gear housing and the DC shaft straight section. I started testing at 3 degrees, and dialed up to 0 in half degree increments.

Hasselblad · 2026-09-15T15:31:20-0600

Bonus question: while I still have an ounce of motivation to fiddle underneath, I plan to replace the rear sway links (noisy rattle AF), with only the OME spring lift will I need to go longer than stock length?

macleanflood · 2026-09-15T18:31:05-0600

I went with some Rugged Ridge rear swaybar links for a 4 inch lift.

-Mac

jjvw · 2026-09-15T18:35:07-0600

Hasselblad said:
It's currently at 0 degrees. Double/triple checked with digital gauges. Went off the flat back of the gear housing and the DC shaft straight section. I started testing at 3 degrees, and dialed up to 0 in half degree increments.

Rear pinion generally should be slightly low so that it stays closer to zero on the highway when the axle is under load. Odd exceptions do exist, though.

CMBD · 2026-09-15T20:16:27-0600

What does your front pinion angle look like?

Rickyd · 2026-09-15T20:40:58-0600

If your profile list is still accurate i have close to the same setup. But with a np231.

I didn't need to raise the motor even more to get the vibes settled. How old are the joints and centering ball in the rear shaft?

Motor Mount Height Question

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