Help identifying noise, spyder gears bad?

[Jahernandez90]

Jeep JLUR 2018
71k miles
Metalcloak adjustable upper and lower F/R short arms, skids.
Rock Krawler 3.5in coils
Falcon 2.5 to 3.5 shocks
Apex steering boost kit
Synergy Sector Shaft Brace
Aluminum tie rod, Reid Knuckles, Dynatrac BJs.
RCV front, chromolies rear both trussed with C gussets.
40 inch MT02 Patagonias non beadlocked.



About two months ago I went offroading/rock crawling. After airing up and getting on the pavement I noticed a grinding/howling noise coming from bottom of my jeep when coasting/deceleration. No issues during acceleration. After a thorough inspection I realized the noise was coming from the rear axle. But I can't figure out exactly where. I jacked up the rear and had my brother shift it to drive and accelerate. The noise was more prominent on the rear passenger side but could also be on the dif.

Things I've done:
Inspected both axle shafts everything looked good, flange, bearings etc.

Inspected driveshafts, no movement on pinion, driveshaft.

Removed dif cover and checked oil for metal shavings, chunks, all good .

Friend 100% sure it was a bent flange on rear passenger shaft so I ordered a new one, no difference but I think the noise went down a little bit.

Took it to an offroad shop and they didn't see anything wrong other than my brake pads being worn out on the edges considerably more than the center. They checked the ring and pinion, backlash was perfect. they think it's the spyder gears or something inside the locker but they did not dissasemble it because they don't know if it's serviceable.

The noise is way more noticeable with the tire on, with the tire off you can barely hear any grinding.

Also, after getting my jeep back from them I got a "service axle locker system" light when I tried to engage the rear locker. They said to bring it back to check it but it's my daily and I don't have time to do so right now. I did check the locker cable and purchased a Z automotive bypass cable and it did nothing. I think that the sensor got oil and metal inside when they removed the diff for inspection.

Jeep works fine on 4low, 4hi drives perfect. So far I have driven around 800 miles after the noise started.

Sponsored

 

[Jahernandez90]

Bump

 

[58Willys]

Hard to tell from the video. Start checking wheel runout, axle runout, check bearings, bent caliper or bent mounting, bent dust shield, etc… One thing at a time.

 

[txj2go]

Rear suspension is relatively simple- a couple of gears in the middle, a couple of long shafts with bearings on the outside. Spyder gears don't even come into play unless you are going around a corner or something similar where tire on one side is turning faster than tire on the other side, likewise anything to do with the locker. With the Jeep up in the air and both rear wheels turning you could certainly have one side turning at a different speed from the other, but driving down the road in a straight line this doesn't happen a significant amount.

Wheel bearings are the logical thing to check but you said they have already been checked. Even worn wheel bearings shouldn't make noise with the vehicle in the air and no load on the tires.

If you are concerned about something funny with the brakes you can take the disks off and spin the tires that way. If the axle flange was bent there should be some runout visible in the wheel when turning.

I had noise in the front of my wife's grand cherokee many years ago. I took it to a big shop in town that specialized in driveline work. They did a lot to the axle including changing ring and pinion, then they discovered the noise was coming from u-joints in the driveshat. Unless you are using a stethoscope it can be hard to track down where noises are really coming from.

 

[azwjowner]

I don’t think the lockers are serviceable but if you’re running 40s on stock axles it wouldn't be surprising that the gears are worn out. You may have toasted a pinion bearing too. I would upgrade to a Dana 60, personally.

 

[Jahernandez90]

Hard to tell from the video. Start checking wheel runout, axle runout, check bearings, bent caliper or bent mounting, bent dust shield, etc… One thing at a time.

Yeah my mechanic checked almost everything except the spyder gears. He didn't want to mess with the locker. He did check all bearing and backlash and everything was good according to him.

 

[Jahernandez90]

I don’t think the lockers are serviceable but if you’re running 40s on stock axles it wouldn't be surprising that the gears are worn out. You may have toasted a pinion bearing too. I would upgrade to a Dana 60, personally.

Gears are good no metal chunks or wear on ring and pinion. Mechanic checked backlash that's why he suspects spyder gears could be the issue. I was almost positive that it could be something with the pinion bearing and driveshaft. But he did check the pinion bearing said it was good as new.

 

[Jahernandez90]

Rear suspension is relatively simple- a couple of gears in the middle, a couple of long shafts with bearings on the outside. Spyder gears don't even come into play unless you are going around a corner or something similar where tire on one side is turning faster than tire on the other side, likewise anything to do with the locker. With the Jeep up in the air and both rear wheels turning you could certainly have one side turning at a different speed from the other, but driving down the road in a straight line this doesn't happen a significant amount.

Wheel bearings are the logical thing to check but you said they have already been checked. Even worn wheel bearings shouldn't make noise with the vehicle in the air and no load on the tires.

If you are concerned about something funny with the brakes you can take the disks off and spin the tires that way. If the axle flange was bent there should be some runout visible in the wheel when turning.

I had noise in the front of my wife's grand cherokee many years ago. I took it to a big shop in town that specialized in driveline work. They did a lot to the axle including changing ring and pinion, then they discovered the noise was coming from u-joints in the driveshat. Unless you are using a stethoscope it can be hard to track down where noises are really coming from.

Yeah he owns an offroad shop but I might have to take it to a shop that specializes in driveline stuff like you did. He did regear my axles so that's why I took my jeep to him. I do suspect that it could be the rear driveshaft and I am planning on replacing it anyways. I do have an Adams driveshaft in the front so might as well change the rear. I ordered a Mopar locker sensor kit yesterday hopefully I can bring my lockers back to life with that.

He was so sure that's it's the spyder gears that he recommend buying a new locker. But I would hate to spend close to $2k on a new locker and labor just to end up with the same noise..

 

[azwjowner]

He was so sure that's it's the spyder gears that he recommend buying a new locker. But I would hate to spend close to $2k on a new locker and labor just to end up with the same noise..

Don’t do it! @wibornz , please talk this gentleman out of replacing his Rubicon locker when he’s running 40s.

(He trashed locker after locker towing on 37s).

 

[roaniecowpony]

If you want to check your spider gears without removing the cover, jack both wheels off the ground and turn one by hand, with the transmission in gear(manual) or park (auto). With the driveshaft unable to turn while you rotate a tire, it forces the spider gears to drive the opposite tire in the other direction. You should hear/feel the spider gears. Some feel/noise is normal. Grinding, sticking, crunching, is not normal.

 

[roaniecowpony]

If your spider gears are bad, you need to replace the differential carrier. Unfortunately, Jeep doesn't sell the carrier for the JL. You can buy the diff carrier from Dana-Spicer listed as a Bronco part under the number in the picture below. It's the identical part and even carries the same Dana Spicer part number as the Jeep's part.

If your locker actuator is bad, this part is also not available from Jeep. It is also not available from Dana Spicer.

I have fitted a Bronco locker actuator into my front axle recently. It fits even with the OEM diff carrier. However, it requires changing the connector on the Bronco actuator to one that fits the Jeep passthrough connector on the axle housing. The locker on the Jeep JL uses a Hall effect sensor to give feedback to the Drive Train Control Module (DTCM). The Bronco doesn't have a position sensor for the locker. So, you need to fool the DTCM with one of the Z-Automotive locker sensor jumpers.

 

[roaniecowpony]

If you decide to pull the cover to inspect the spider gears, you can look through the round holes on the diff carrier and see the spider gears. You can watch them rotate when you rotate a tire.

 

[Jahernandez90]

M

If your spider gears are bad, you need to replace the differential carrier. Unfortunately, Jeep doesn't sell the carrier for the JL. You can buy the diff carrier from Dana-Spicer listed as a Bronco part under the number in the picture below. It's the identical part and even carries the same Dana Spicer part number as the Jeep's part.

If your locker actuator is bad, this part is also not available from Jeep. It is also not available from Dana Spicer.

I have fitted a Bronco locker actuator into my front axle recently. It fits even with the OEM diff carrier. However, it requires changing the connector on the Bronco actuator to one that fits the Jeep passthrough connector on the axle housing. The locker on the Jeep JL uses a Hall effect sensor to give feedback to the Drive Train Control Module (DTCM). The Bronco doesn't have a position sensor for the locker. So, you need to fool the DTCM with one of the Z-Automotive locker sensor jumpers.

Buying a bronco carrier would require rechecking backlash and pinion depth anyways right? At that point might as well get something like an OX locker unless I am wrong. I ordered the sensor kit if that doesn't fix my locker I might give that actuator hack a try only if I am 100% sure that there is no mechanical issues with my differential.

It was working before dropping it off at the shop so they either installed something wrong or my sensor got oil and metal particles on it causing it to malfunction. I did check for noise on the gears and the two gears I can see look good as new (video). When rotating the tire they sound good. But halfway through the video if I rotate the tires back and forth quickly I hear like a clunky noise. I am not sure if that's normal or not. Thanks.

Link:

 

[azwjowner]

Buying a bronco carrier would require rechecking backlash and pinion depth anyways right? At that point might as well get something like an OX locker unless I am wrong.

You don't have to change pinion depth to swap in a locker or carrier. Just backlash. I still say you'd be better long-term with a Dana 60, but OX would probably be the strongest of all the lockers if you insist on keeping the existing axle.

Read this: https://www.jlwranglerforums.com/fo...i-think-it-has-been-unreliable-for-me.118652/

He went with a Fusion 60.

 

[Jahernandez90]

You don't have to change pinion depth to swap in a locker or carrier. Just backlash. I still say you'd be better long-term with a Dana 60, but OX would probably be the strongest of all the lockers if you insist on keeping the existing axle.

Read this: https://www.jlwranglerforums.com/fo...i-think-it-has-been-unreliable-for-me.118652/

He went with a Fusion 60.

Since my ring and pinion didn't get any damage at all after wheeling hard fully locked bouncing on rocks etc for over 10k miles on 38s and around 4k miles on 40s I am gonna keep trying to figure out the issue before spending over $7k on a Fusion bolt on axle which I was considering. Instead of spending $2k on a new locker and labor and possibly having another locker failure, ring and pinion failure or bent axle might as well bite the bullet and run a 44/60 setup.

But if I can solve my issue without having to get a new carrier (Locker sensor kit fixes my lockers and spyder gears are good, noise is a bearing or driveshaft issue) then I will keep the 44 rear.

You know what they say "find it before it finds you", I low-key wish it would find me already to give me peace of mind, tow it to the shop and fix it.

Sponsored