I just changed the diff fluid on my 3500 Dodge with Swepco 80w140. I now am told that AAM axles spec a 75w90...Will i be OK or do i need to chnage it out? The truck is used for trailer towing, approx 12,000 pounds. Does anyone know why AAM would spec a 75w90?
rear diff viscosity/new Doge Cummins 3500
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u will be fine, especially with the load you'll be putting on it, your differential will be getting plenty warm.
Originally Posted By: oliver88
I just changed the diff fluid on my 3500 Dodge with Swepco 80w140. I now am told that AAM axles spec a 75w90...Will i be OK or do i need to chnage it out? The truck is used for trailer towing, approx 12,000 pounds. Does anyone know why AAM would spec a 75w90?
Swepco makes a very good gear oil. If you change it again, use the Swepco 201.
I just changed the diff fluid on my 3500 Dodge with Swepco 80w140. I now am told that AAM axles spec a 75w90...Will i be OK or do i need to chnage it out? The truck is used for trailer towing, approx 12,000 pounds. Does anyone know why AAM would spec a 75w90?
Swepco makes a very good gear oil. If you change it again, use the Swepco 201.
Originally Posted By: oliver88
I just changed the diff fluid on my 3500 Dodge with Swepco 80w140. I now am told that AAM axles spec a 75w90...Will i be OK or do i need to chnage it out? The truck is used for trailer towing, approx 12,000 pounds. Does anyone know why AAM would spec a 75w90?
I'm running 85w140 Royal Purple in my 04 ram...I've got almost 90k on it with nothing but good results.
I just changed the diff fluid on my 3500 Dodge with Swepco 80w140. I now am told that AAM axles spec a 75w90...Will i be OK or do i need to chnage it out? The truck is used for trailer towing, approx 12,000 pounds. Does anyone know why AAM would spec a 75w90?
I'm running 85w140 Royal Purple in my 04 ram...I've got almost 90k on it with nothing but good results.
Try the Amsoil SVG 75w110 next time.
Originally Posted By: unDummy
So, I guess knowing more then the engineers is OK here.
If you plan on sticking with the 75w90, check around for improved cooling/capacity diff cover.
I changed after they issued an internal memo stating that 75w140 was recommended for towing...
I don't work for Dodge, so I don't have the memo.
So, I guess knowing more then the engineers is OK here.
If you plan on sticking with the 75w90, check around for improved cooling/capacity diff cover.
I changed after they issued an internal memo stating that 75w140 was recommended for towing...
I don't work for Dodge, so I don't have the memo.
Originally Posted By: unDummy
So, I guess knowing more then the engineers is OK here.
When I started owt I couldn't even spel enjaneer...now I are one.
BTW, You can get a finned diff cover at Summit Racing
So, I guess knowing more then the engineers is OK here.
When I started owt I couldn't even spel enjaneer...now I are one.
BTW, You can get a finned diff cover at Summit Racing
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Originally Posted By: oliver88
Does anyone know why AAM would spec a 75w90?
Most likely 1 of 2 possible reasons:
1. 2/3rds of the guys at AAM are idiots left over from GM
2. The bearings might not like the thicker viscosity. AAM has lots of diff carrier bearing issues because they discarded most of the proven designs of the past to make it "better" (cheaper).
Does anyone know why AAM would spec a 75w90?
Most likely 1 of 2 possible reasons:
1. 2/3rds of the guys at AAM are idiots left over from GM
2. The bearings might not like the thicker viscosity. AAM has lots of diff carrier bearing issues because they discarded most of the proven designs of the past to make it "better" (cheaper).
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