There's a poll attached to this thread. For the sake of clarity the poll is designed to ask how you actually resealed your differential(s) ie: what FIPG, RTV or gasket was used. Please don't vote if you haven't done the job yourself. However, if either of your differentials have been serviced (taken out, reinstalled) by a mechanic/other person and if the method used to seal it is known (gasket, FIPG, etc) then take the poll.
Once you've indicated which method you used to reseal/reinstall your diff you should then post up details ie: Rear Diff, flanges cleaned (how), no corrosion or damage found, Bob's Super Balls RTV applied to OEM gasket, 8 years ago, no leaks, ----.
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Wanted to start this thread in order to get the hive mind experience in one place. It's been discussed in a few threads over the years and the general consensus seems to be that the OEM gasket by itself can seal well if the surface is clean and doesn't have corrosion/pitting/damage and if the diff is not subjected to any significant impacts (ie: on road use only). Also that using the gasket by itself may be more prone to leaks particularly in the front differential (80 series) which appears to be more prone to loosening up (compared to the rear diff) when the OEM gasket is used.
Seems like some mechanics and others with experience resealing reinstaling differentials often use RTV instead of the gasket.
Interesting trivia about the Hondabond HT: the packaging lists the Effective Temperature range as 75'F to 600'F, so that makes me wonder if the +75'F isn't a typo?? ie: -75'F seems too low but +75'F seems too high for the bottom end of the useful range?? IDK (checking with Honda, will edit when I get an answer).
One area of disagreement/discussion when using the OEM gasket is whether or not to apply anything over the gasket. Some say a light coating of RTV, some say absolutely do not put RTV over the diff gasket (ie: Permatex and Loctite both advise to not put RTV over a gasket unless just at an edge or corner as is some applications, but not our diffs). And then some sealant manufacturers may say a very light coat of something like High Tack gasket dressing/sealant (sprayed on) is OK.
Many RTV or gasket dressing products say they're resistant to "oil" or "chemicals" but some don't specifically state whether or not they're approved to use with exposure to Hypoid Gear oil with EP additives. IME the only way to find out is to contact the manufacturer of the product, but that is often very difficult ie: Hondabond and Yamabond are both made by ThreeBond and I tried getting that info but haven't heard back yet.
Permatex for example stated (personal communication from their tech dept) that the only Permatex RTV that should be used on a differential or gear box exposed to Hypoid/EP Gear oil is their Gear Oil Gasket Maker, not their Ultra Grey product (the Gear Oil Gasket Maker is a newer product). But then many people have used the Ultra Grey to seal their diffs, so there's that.
How much RTV to apply? If not enough and it may not seal, too much and it may end up (peeling off) inside the differential. And then there's the mess when removing RTV when you next dismount the diff carrier and how to remove the old sealant?? A plain gasket is probably the easiest to clean up.
Photo below shows a few examples of RTV and one gasket dressing (the Versachem Prime Seal product in the white bottle is the exact same product as Permatex Aviation gasket sealer #3, in this application it would only be used as a gasket dressing, not by itself)
FWIW there's a newish type of gasket made by LubeLocker which has a thin aluminum core covered by a type of rubber gasket material which is itself then coated with lines of sealant; seems like a good design. Unfortunately the company does not offer a gasket to fit our differentials (maybe if more people called the company and requested they add one for the 80 series??).
So just tossing out these questions for discussion. Have fun.
Once you've indicated which method you used to reseal/reinstall your diff you should then post up details ie: Rear Diff, flanges cleaned (how), no corrosion or damage found, Bob's Super Balls RTV applied to OEM gasket, 8 years ago, no leaks, ----.
-------------------------------------------------------------------------------
Wanted to start this thread in order to get the hive mind experience in one place. It's been discussed in a few threads over the years and the general consensus seems to be that the OEM gasket by itself can seal well if the surface is clean and doesn't have corrosion/pitting/damage and if the diff is not subjected to any significant impacts (ie: on road use only). Also that using the gasket by itself may be more prone to leaks particularly in the front differential (80 series) which appears to be more prone to loosening up (compared to the rear diff) when the OEM gasket is used.
Seems like some mechanics and others with experience resealing reinstaling differentials often use RTV instead of the gasket.
Interesting trivia about the Hondabond HT: the packaging lists the Effective Temperature range as 75'F to 600'F, so that makes me wonder if the +75'F isn't a typo?? ie: -75'F seems too low but +75'F seems too high for the bottom end of the useful range?? IDK (checking with Honda, will edit when I get an answer).
One area of disagreement/discussion when using the OEM gasket is whether or not to apply anything over the gasket. Some say a light coating of RTV, some say absolutely do not put RTV over the diff gasket (ie: Permatex and Loctite both advise to not put RTV over a gasket unless just at an edge or corner as is some applications, but not our diffs). And then some sealant manufacturers may say a very light coat of something like High Tack gasket dressing/sealant (sprayed on) is OK.
Many RTV or gasket dressing products say they're resistant to "oil" or "chemicals" but some don't specifically state whether or not they're approved to use with exposure to Hypoid Gear oil with EP additives. IME the only way to find out is to contact the manufacturer of the product, but that is often very difficult ie: Hondabond and Yamabond are both made by ThreeBond and I tried getting that info but haven't heard back yet.
Permatex for example stated (personal communication from their tech dept) that the only Permatex RTV that should be used on a differential or gear box exposed to Hypoid/EP Gear oil is their Gear Oil Gasket Maker, not their Ultra Grey product (the Gear Oil Gasket Maker is a newer product). But then many people have used the Ultra Grey to seal their diffs, so there's that.
How much RTV to apply? If not enough and it may not seal, too much and it may end up (peeling off) inside the differential. And then there's the mess when removing RTV when you next dismount the diff carrier and how to remove the old sealant?? A plain gasket is probably the easiest to clean up.
Photo below shows a few examples of RTV and one gasket dressing (the Versachem Prime Seal product in the white bottle is the exact same product as Permatex Aviation gasket sealer #3, in this application it would only be used as a gasket dressing, not by itself)
FWIW there's a newish type of gasket made by LubeLocker which has a thin aluminum core covered by a type of rubber gasket material which is itself then coated with lines of sealant; seems like a good design. Unfortunately the company does not offer a gasket to fit our differentials (maybe if more people called the company and requested they add one for the 80 series??).
So just tossing out these questions for discussion. Have fun.
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