Amsoil SVG causing rear diff chatter?
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Originally Posted By: dave123
I have had best luck with MC FM when needed in any app most only needed .5oz per QT gear lube to fix chatter.
Yes the Blue Oval XL-3 stuff does seem to be the MOST potent (like almost TWICE as potent as everyone else's).
It is also the MOST pungent and pervasive as far as odor goes as well!!
I have had best luck with MC FM when needed in any app most only needed .5oz per QT gear lube to fix chatter.
Yes the Blue Oval XL-3 stuff does seem to be the MOST potent (like almost TWICE as potent as everyone else's).
It is also the MOST pungent and pervasive as far as odor goes as well!!
Chances are this is mostly a straight road vehicle. You can and should add some more Slip-Lock or even some of the Ford additive.
Redline gear oil never let me down, ever, and I hope it keep it that way. I try many other synthetic gear oil from, mobil 1 to amsoils to RP, all them require a little bit of ford or gm depend on which car I drive, only redline is the only oil never need add any extra fric, it have the correct fric right out the bottle.
I have Mobil 1 gear oil and Ford FM in my LS Ford rear, never a problem with chatter.
I would try adding more FM if that's what Amsoil suggests. If the additional FM doesn't work I'd swap out the fluid, and go back to what you were using before. No point in wrecking it trying to sort things out.
I would try adding more FM if that's what Amsoil suggests. If the additional FM doesn't work I'd swap out the fluid, and go back to what you were using before. No point in wrecking it trying to sort things out.
Originally Posted By: Pablo
Chances are this is mostly a straight road vehicle. You can and should add some more Slip-Lock or even some of the Ford additive.
The GF drives the truck and seeing how I'm 400 miles from home, I just got my neighbor to go over and add another half bottle of Slip-Lok. Hopefully the GF will report back to me if its still chattering. Keep you posted.
Chances are this is mostly a straight road vehicle. You can and should add some more Slip-Lock or even some of the Ford additive.
The GF drives the truck and seeing how I'm 400 miles from home, I just got my neighbor to go over and add another half bottle of Slip-Lok. Hopefully the GF will report back to me if its still chattering. Keep you posted.
Originally Posted By: atc250r
Originally Posted By: Pablo
Chances are this is mostly a straight road vehicle. You can and should add some more Slip-Lock or even some of the Ford additive.
The GF drives the truck and seeing how I'm 400 miles from home, I just got my neighbor to go over and add another half bottle of Slip-Lok. Hopefully the GF will report back to me if its still chattering. Keep you posted.
I start feeling it be arite, if it still noise, add whole bottle of it, btw u got a cool neighbor, if I was their i im glad to help too.
Originally Posted By: Pablo
Chances are this is mostly a straight road vehicle. You can and should add some more Slip-Lock or even some of the Ford additive.
The GF drives the truck and seeing how I'm 400 miles from home, I just got my neighbor to go over and add another half bottle of Slip-Lok. Hopefully the GF will report back to me if its still chattering. Keep you posted.
I start feeling it be arite, if it still noise, add whole bottle of it, btw u got a cool neighbor, if I was their i im glad to help too.
What you guys are forgetting is that a little chatter you feel, more than hear, is good. The clutches are not slipping excessively and the traction unit is going to give more lockup.
When you have loud pops that sound like parts breaking, that's obviously a drivability issue (even though it dosent really hurt anything).
If you have your traction unit so watered down that it barely works, what's the point?
When you have loud pops that sound like parts breaking, that's obviously a drivability issue (even though it dosent really hurt anything).
If you have your traction unit so watered down that it barely works, what's the point?
Originally Posted By: Rand
chatter is usually related to FM not really to viscosity..
otherwise the chattering would change wildly based on outside air temp.
For a high spring tension unit with no FM, it wont make any noise (this varies with clutch facing) until it really warms up. Then it will pop like crazy. You will think something is breaking, although it's okay.
Add any FM and it goes back to livable almost instantly.
The more worn the side gears are the more pop you will hear.
chatter is usually related to FM not really to viscosity..
otherwise the chattering would change wildly based on outside air temp.
For a high spring tension unit with no FM, it wont make any noise (this varies with clutch facing) until it really warms up. Then it will pop like crazy. You will think something is breaking, although it's okay.
Add any FM and it goes back to livable almost instantly.
The more worn the side gears are the more pop you will hear.
Originally Posted By: Jeff_in_VABch
Originally Posted By: Rand
chatter is usually related to FM not really to viscosity..
otherwise the chattering would change wildly based on outside air temp.
For a high spring tension unit with no FM, it wont make any noise (this varies with clutch facing) until it really warms up. Then it will pop like crazy. You will think something is breaking, although it's okay.
Add any FM and it goes back to livable almost instantly.
The more worn the side gears are the more pop you will hear.
Isn't the popping caused by binding? If so isn't that hard on the U joints? Either way its a condition I'd rather not have. BTW these are questions I'm not looking to fight, just looking for an answer. Thanks
Originally Posted By: Rand
chatter is usually related to FM not really to viscosity..
otherwise the chattering would change wildly based on outside air temp.
For a high spring tension unit with no FM, it wont make any noise (this varies with clutch facing) until it really warms up. Then it will pop like crazy. You will think something is breaking, although it's okay.
Add any FM and it goes back to livable almost instantly.
The more worn the side gears are the more pop you will hear.
Isn't the popping caused by binding? If so isn't that hard on the U joints? Either way its a condition I'd rather not have. BTW these are questions I'm not looking to fight, just looking for an answer. Thanks
Originally Posted By: digitalSniperX1
Amsoil says their gear oils do not require any friction modifier additions but I swear I hear chatter when turning around for example and accelerating quickly at the same time. Is this possible in something with an engine with wimpy torque output (rotary in an RX-8)?
You say "accelerating quickly" so my answer is predicated on that. To a large degree, this is NORMAL for a clutch (plate or cone) type limited slip. When you apply torque to a LSD, gear separation forces between the side and pinion (spider) gears pushes the side gears outboard and increases the built in clamping force (preload) in the clutch packs. This decreases the differentiation and increases the bias. In other words, applying power makes the unit tighten up (come closer to a splitting the torque equally side to side). In a turn, of course, the outer and inner wheels travel at different speeds, so something has to give... either a tire has to slip or the clutches will. If you have sticky tires, it's likely you are feeling the breakaway of the clutches. They shouldn't chatter under a light load but they will often chatter when breakaway occurs under a high torque load.
Friction modifier may decrease this but it may also decrease the effectiveness of the LSD. If this is something you feel only when you are driving with spirit, then I'd say let it go. If you were to feel it in normal, sedate driving, then you should address it with adding small amounts of FM (1/4 oz at a time), doing some figure eights in a parking lot to distribute it well in the oil, drive for a while and note the change. Repeat as necessary.
Don't use any more FM than you need. Certain types of FMs are organic in nature and do not handle heat well. They oxidize more quickly than the oil and take the oil down with them. I don't know exactly how Amsoil's is made but would predict it's an upper end product. The cheap stuff you buy a the parts store is likely the less expensive organic stuff.
Amsoil says their gear oils do not require any friction modifier additions but I swear I hear chatter when turning around for example and accelerating quickly at the same time. Is this possible in something with an engine with wimpy torque output (rotary in an RX-8)?
You say "accelerating quickly" so my answer is predicated on that. To a large degree, this is NORMAL for a clutch (plate or cone) type limited slip. When you apply torque to a LSD, gear separation forces between the side and pinion (spider) gears pushes the side gears outboard and increases the built in clamping force (preload) in the clutch packs. This decreases the differentiation and increases the bias. In other words, applying power makes the unit tighten up (come closer to a splitting the torque equally side to side). In a turn, of course, the outer and inner wheels travel at different speeds, so something has to give... either a tire has to slip or the clutches will. If you have sticky tires, it's likely you are feeling the breakaway of the clutches. They shouldn't chatter under a light load but they will often chatter when breakaway occurs under a high torque load.
Friction modifier may decrease this but it may also decrease the effectiveness of the LSD. If this is something you feel only when you are driving with spirit, then I'd say let it go. If you were to feel it in normal, sedate driving, then you should address it with adding small amounts of FM (1/4 oz at a time), doing some figure eights in a parking lot to distribute it well in the oil, drive for a while and note the change. Repeat as necessary.
Don't use any more FM than you need. Certain types of FMs are organic in nature and do not handle heat well. They oxidize more quickly than the oil and take the oil down with them. I don't know exactly how Amsoil's is made but would predict it's an upper end product. The cheap stuff you buy a the parts store is likely the less expensive organic stuff.
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Well I now have 2 complete bottle of Slip-Lok additive in the diff and it still chatters. I have a couple tubes of the additive here at home, so I guess I'll add a couple ounces one day this week and see what happens. Not impressed.
Originally Posted By: atc250r
Well I now have 2 complete bottle of Slip-Lok additive in the diff and it still chatters. I have a couple tubes of the additive here at home, so I guess I'll add a couple ounces one day this week and see what happens. Not impressed.
I'd drain and refill with another brand of gear oil, there's only so much of that Slip-Lok additive you can put in that differential. If it continues to chatter you might have problems with the differential. JMO
Well I now have 2 complete bottle of Slip-Lok additive in the diff and it still chatters. I have a couple tubes of the additive here at home, so I guess I'll add a couple ounces one day this week and see what happens. Not impressed.
I'd drain and refill with another brand of gear oil, there's only so much of that Slip-Lok additive you can put in that differential. If it continues to chatter you might have problems with the differential. JMO
I called Amsoil's tech line and the gentleman I spoke with had to run my situation by a higher-up while I waited on hold. When he came back to the phone, I was told to add 1 more ounce of Slip-Lok and if that didn't work, they didn't know what to tell me. Claims they had never heard of such a situation.
So I added a another ounce (partial 3rd bottle) and now it seems to be quiet. Still not very comfortable about this situation. I strongly DO NOT RECOMMEND SLIP-LOK additive. I wish I had used Motorcraft friction modifier.
So I added a another ounce (partial 3rd bottle) and now it seems to be quiet. Still not very comfortable about this situation. I strongly DO NOT RECOMMEND SLIP-LOK additive. I wish I had used Motorcraft friction modifier.
Originally Posted By: atc250r
I called Amsoil's tech line and the gentleman I spoke with had to run my situation by a higher-up while I waited on hold. When he came back to the phone, I was told to add 1 more ounce of Slip-Lok and if that didn't work, they didn't know what to tell me. Claims they had never heard of such a situation.
So I added a another ounce (partial 3rd bottle) and now it seems to be quiet. Still not very comfortable about this situation. I strongly DO NOT RECOMMEND SLIP-LOK additive. I wish I had used Motorcraft friction modifier.
If you are not satisfied, you are suppose to get your money back. I think that was/is Amsoils policy.
I called Amsoil's tech line and the gentleman I spoke with had to run my situation by a higher-up while I waited on hold. When he came back to the phone, I was told to add 1 more ounce of Slip-Lok and if that didn't work, they didn't know what to tell me. Claims they had never heard of such a situation.
So I added a another ounce (partial 3rd bottle) and now it seems to be quiet. Still not very comfortable about this situation. I strongly DO NOT RECOMMEND SLIP-LOK additive. I wish I had used Motorcraft friction modifier.
If you are not satisfied, you are suppose to get your money back. I think that was/is Amsoils policy.
Update! So this past week the limited slip "chatter" came back. I haven't been comfortable with the 9 ounces of SlipLok I had to add only 15 short months ago. So yesterday I drained out all that Amsoil 75W-140 and replaced with Syngard 75W-140.
http://www.crossoil.com/syngard_gear_oils.php
It says in big bold lettering right on the front of the bottles that it meets Ford specs for the trucks. I also bought Motorcraft additive, but so far the diff is quiet and doesn't appear to need any additive.
I have had very good results with Amsoil 75W-90 oils, but this 140 grade was nothing but a head ache for me. Not sure why it required 9 ounces of additive in the first place, let alone why the chatter came back after 1 year and only about 5000 miles of no-load driving.
I just hope no damage to my clutches/gears have occurred from this fiasco...
http://www.crossoil.com/syngard_gear_oils.php
It says in big bold lettering right on the front of the bottles that it meets Ford specs for the trucks. I also bought Motorcraft additive, but so far the diff is quiet and doesn't appear to need any additive.
I have had very good results with Amsoil 75W-90 oils, but this 140 grade was nothing but a head ache for me. Not sure why it required 9 ounces of additive in the first place, let alone why the chatter came back after 1 year and only about 5000 miles of no-load driving.
I just hope no damage to my clutches/gears have occurred from this fiasco...
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