98 Durango Grind/Growl on corners forward/reverse low speed
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Amateur
Joined: Jul 2012
Posts: 32
Likes: 0
From: Colorado
Huzzah! I have narrowed it down to a problem in the differential.
The limited slip is locked/dragging. I got the truck in the air to do the spin test and the wheels wouldn't turn at all -I know I left it in park, so I repeated the test in neutral and they spun the same direction. The growl/vibration on corners is from the diff being forced to function as it should, I think.
I checked the temperature with a pyrometer, forty-five minutes after driving and the cover was still at 109.5 degrees with a shop fan having been blowing on it almost the entire time. By spec, the upper temp limit is ~200, so I believe there is an excessive heat issue caused by the binding.
Maybe, I didn't have the gasket/oil/additive to pull the cover off. Lash is good on the pinion-ring mesh, as is the endplay.
I know the front diff needs work, as the pinion seal is leaking and the lash is excessive.
The limited slip is locked/dragging. I got the truck in the air to do the spin test and the wheels wouldn't turn at all -I know I left it in park, so I repeated the test in neutral and they spun the same direction. The growl/vibration on corners is from the diff being forced to function as it should, I think.
I checked the temperature with a pyrometer, forty-five minutes after driving and the cover was still at 109.5 degrees with a shop fan having been blowing on it almost the entire time. By spec, the upper temp limit is ~200, so I believe there is an excessive heat issue caused by the binding.
Maybe, I didn't have the gasket/oil/additive to pull the cover off. Lash is good on the pinion-ring mesh, as is the endplay.
I know the front diff needs work, as the pinion seal is leaking and the lash is excessive.
Huzzah! I have narrowed it down to a problem in the differential.
The limited slip is locked/dragging. I got the truck in the air to do the spin test and the wheels wouldn't turn at all -I know I left it in park, so I repeated the test in neutral and they spun the same direction. The growl/vibration on corners is from the diff being forced to function as it should, I think.
I checked the temperature with a pyrometer, forty-five minutes after driving and the cover was still at 109.5 degrees with a shop fan having been blowing on it almost the entire time. By spec, the upper temp limit is ~200, so I believe there is an excessive heat issue caused by the binding.
Maybe, I didn't have the gasket/oil/additive to pull the cover off. Lash is good on the pinion-ring mesh, as is the endplay.
I know the front diff needs work, as the pinion seal is leaking and the lash is excessive.
The limited slip is locked/dragging. I got the truck in the air to do the spin test and the wheels wouldn't turn at all -I know I left it in park, so I repeated the test in neutral and they spun the same direction. The growl/vibration on corners is from the diff being forced to function as it should, I think.
I checked the temperature with a pyrometer, forty-five minutes after driving and the cover was still at 109.5 degrees with a shop fan having been blowing on it almost the entire time. By spec, the upper temp limit is ~200, so I believe there is an excessive heat issue caused by the binding.
Maybe, I didn't have the gasket/oil/additive to pull the cover off. Lash is good on the pinion-ring mesh, as is the endplay.
I know the front diff needs work, as the pinion seal is leaking and the lash is excessive.
Hall Of Fame
Joined: Jun 2005
Posts: 14,228
Likes: 19
From: Riverton, UT
You say you didn't have the lubricants to pull the cover off (you don't need a gasket), yet you can measure the backlash, you are a magician!
You say it has LS, and the shop said it doesn't, you spun the wheels and they went the same dirrection. Well all that states;
YOU HAVE A LIMITED SLIP REAR DIFFERENTIAL! Pull some 7oz of the fluid out and replace it with a bottle of Friction Modifier. Don't drive it until you get it in there as you are wearing out the clutch packs and that will take out the diff!
Auto Zone sells a 7oz bottle for about $7, use the whole thing. It's located back next to the oil on a side cap. What you are feeling is the clutch packs on the rear are locking up and "shuddering" when the clutches are engaged, which it will do if the Friction Modifier isn't used. What the Friction Modifier does is lubricate the clutch packs while they are being applied, hints the "shuddering" you are feeling. And hints the name Friction Modifier.
Now it will only be the rear differential (being LS) as the front end was never made in LS and shouldn't used in a front end anyway. It was only made in Open Gearing so no Friction Modifier in the front.
Problem solved, happy wrenching!
It's my ma's truck, and she believes that her usual shop -across the street from her work- has no clue what they're doing. I don't know -and really don't believe- that they put the Lube Modifier in the differentials at the last service as they insist that the identification tags are missing/damaged and that it's not equipped with limited slip gearing.
YOU HAVE A LIMITED SLIP REAR DIFFERENTIAL! Pull some 7oz of the fluid out and replace it with a bottle of Friction Modifier. Don't drive it until you get it in there as you are wearing out the clutch packs and that will take out the diff!
Auto Zone sells a 7oz bottle for about $7, use the whole thing. It's located back next to the oil on a side cap. What you are feeling is the clutch packs on the rear are locking up and "shuddering" when the clutches are engaged, which it will do if the Friction Modifier isn't used. What the Friction Modifier does is lubricate the clutch packs while they are being applied, hints the "shuddering" you are feeling. And hints the name Friction Modifier.
Now it will only be the rear differential (being LS) as the front end was never made in LS and shouldn't used in a front end anyway. It was only made in Open Gearing so no Friction Modifier in the front.
Problem solved, happy wrenching!
