The spin on filter is mounted to the Outside of the Transmission Case just behind the bell housing. The internal filter is the one in your pan. The internal filter should be changed and the pan dropped periodically to ensure that this filter has not trapped metal filings which are a tell tale sign of an internal problem, especially when towing a hefty load. Every 60 to 70K miles is a good time to consider doing this flush. Cheap insurance is better then an expensive rebuild that could have been prevented. If you need a rebuild kit, Tech Manual or parts for your Allison rebuild please see our store or ask us we will be glad to accommodate all of your part needs. *If you don't see what you need here, contact us and we will list it here on eBay. We have hundreds of bearing kits and all kinds.
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