Rear end fluid....how often should it be changed?
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From: Ft. Lauderdale, FL, USA
Originally Posted by The Black Mamba
How many miles are on it?
Jeezuz christ.....I better get it changed tomorrow.
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From: Ft. Lauderdale, FL, USA
Originally Posted by Greggy
My feelings, w/ a posi type unit evey 15k to 25k miles depending on use.
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From: Ft. Lauderdale, FL, USA
Originally Posted by Greggy
I bet the fluid looks like metal soup.
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From: Ft. Lauderdale, FL, USA
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I have a Stock 97 Firebird V6. It was my brothers and he ran the **** out of it, doing burns out and donuts like an idiot thinking hes badass even though its a 6 banger. He fianlly got a new car and gave it to me. I Changed the rear end fluid at 143,000 miles. The oil was Cold and it was as thin as water and black as night. But to my suprise the ring and pinion were in great condition.
It depends on the differential type too. If it has a clutch type posi like an Eaton the fluid will tend to be darker, if it has an Auburn cone type you will see more stuff on the magnet, if it's a torque biasing type like a Detroit TruTrac or Torsen the fluid usually comes out clean because theres nothing but gears, no clutches.
I change it more often with an auburn, less with an eaton, and go even longer with a torsen.
I change it more often with an auburn, less with an eaton, and go even longer with a torsen.
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From: Ft. Lauderdale, FL, USA
I have a Stock 97 Firebird V6. It was my brothers and he ran the **** out of it, doing burns out and donuts like an idiot thinking hes badass even though its a 6 banger. He fianlly got a new car and gave it to me. I Changed the rear end fluid at 143,000 miles. The oil was Cold and it was as thin as water and black as night. But to my suprise the ring and pinion were in great condition.
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From: The 'Burgh, PA
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rear end gear oil change interval really does depend on use and carrier/differential type. At 50k on a 3rd gen austrialian 9-bolt, which is stronger than the 10-bolt and a clutch type carrier, the fluid was toast at 50k. In fact, the differential clutchs were 'popping' the axles badly on a slow turn. After replacing the clutch dust contaminated fluid the differential was smooth, but I lost all posi-action at around 80k, and the axle bearings roared like a jet plane at 100k even with regular service oftenafter the late 50k service. This axle should have had service much earlier..say 20-25k.
I have done service on my ls1 torsen since new at 15-20k intervals. Probably can easily double it on this type of posi, but I wanted to keep things going strong for 100+k. Torsens work perfectly untill they break. At 95k I still have great posi-action, but now may be getting some bearing scraping/clicking noises.
So overkill 15k changes still won't make thing last forever, but on some types of differentials 50k is too long to go.
My recomendations for a hard driven street car:
auburn/eaton clutch cone type: Dino GL5 fluid w/ LSD additive at 15-25k miles
zexel torsen/detroit true-trac helical gear type: Synthetic GL5 no LSD additive 25-50k miles.
For me I would use the lower of the two intervals because it is easy and I can keep an eye on things like low levels, wear, inspection of parts.
I have done service on my ls1 torsen since new at 15-20k intervals. Probably can easily double it on this type of posi, but I wanted to keep things going strong for 100+k. Torsens work perfectly untill they break. At 95k I still have great posi-action, but now may be getting some bearing scraping/clicking noises.
So overkill 15k changes still won't make thing last forever, but on some types of differentials 50k is too long to go.
My recomendations for a hard driven street car:
auburn/eaton clutch cone type: Dino GL5 fluid w/ LSD additive at 15-25k miles
zexel torsen/detroit true-trac helical gear type: Synthetic GL5 no LSD additive 25-50k miles.
For me I would use the lower of the two intervals because it is easy and I can keep an eye on things like low levels, wear, inspection of parts.
