I'm curious as to why the manufacturer always says NOT to extend oil change intervals whether or not you use conventional or synthetic oil. I've read a lot of comments on here about the benefit of synthetic oils being extended OCIs. BUT, . . my owners manual specifically says to use 15W-40 conventional OR 5W-40 synthetic CJ4 oil, depending on the temperatures and also points out that the oil change intervals should remain the same whether using conventional or synthetic. Is it just CYA?
Extended Oil Change Intervals with Synthetics
- Thread starter tr4petty
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dnewton3
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YES - It's CYA. It's about covering their posterior in regard to warranty.
OCIs are your cost. Warranty claims are their cost.
Doing the math is easy; they write a policy that places the burden of cost upon you and reduces the risk of warranty claims to them.
OCIs are your cost. Warranty claims are their cost.
Doing the math is easy; they write a policy that places the burden of cost upon you and reduces the risk of warranty claims to them.
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Originally Posted By: dnewton3
YES - It's CYA. It's about covering their posterior in regard to warranty.
OCIs are your cost. Warranty claims are their cost.
Doing the math is easy; they write a policy that places the burden of cost upon you and reduces the risk of warranty claims to them.
+1 They also assume(usually correctly) that no one ever checks their oil level. What's worse - 1 or 2 qts low on conventional after 5k miles.....or 3-4 qts low on synthetic after 10k miles? Chevy increased the sump capacity in their new trucks for the sole reason that people don't check their oil.
YES - It's CYA. It's about covering their posterior in regard to warranty.
OCIs are your cost. Warranty claims are their cost.
Doing the math is easy; they write a policy that places the burden of cost upon you and reduces the risk of warranty claims to them.
+1 They also assume(usually correctly) that no one ever checks their oil level. What's worse - 1 or 2 qts low on conventional after 5k miles.....or 3-4 qts low on synthetic after 10k miles? Chevy increased the sump capacity in their new trucks for the sole reason that people don't check their oil.
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Originally Posted By: tr4petty
I'm curious as to why the manufacturer always says NOT to extend oil change intervals whether or not you use conventional or synthetic oil. I've read a lot of comments on here about the benefit of synthetic oils being extended OCIs. BUT, . . my owners manual specifically says to use 15W-40 conventional OR 5W-40 synthetic CJ4 oil, depending on the temperatures and also points out that the oil change intervals should remain the same whether using conventional or synthetic. Is it just CYA?
going by the claims made on the oil bottles will get you into trouble possibly.
1. Some syn oils claim 10k plus OCI is ok wiht their product, my 08 dmax is known to kill the oil with diesel contamination due to DPF cycle.
So extending the OCI without understanding your engine and sampling at proper interval might land you in trouble.
Then you are fighting a finger pointing game with the dealership.
OCI is cheap, 2 gallons of oil costs 20$, why take chances?
Don't forget UOA costs $$ too.
I'm curious as to why the manufacturer always says NOT to extend oil change intervals whether or not you use conventional or synthetic oil. I've read a lot of comments on here about the benefit of synthetic oils being extended OCIs. BUT, . . my owners manual specifically says to use 15W-40 conventional OR 5W-40 synthetic CJ4 oil, depending on the temperatures and also points out that the oil change intervals should remain the same whether using conventional or synthetic. Is it just CYA?
going by the claims made on the oil bottles will get you into trouble possibly.
1. Some syn oils claim 10k plus OCI is ok wiht their product, my 08 dmax is known to kill the oil with diesel contamination due to DPF cycle.
So extending the OCI without understanding your engine and sampling at proper interval might land you in trouble.
Then you are fighting a finger pointing game with the dealership.
OCI is cheap, 2 gallons of oil costs 20$, why take chances?
Don't forget UOA costs $$ too.
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Additionally, OEMs have little control over starting TBN of the lube if going by a basic CJ-4 specification. Those can be anywhere from 7 on up. Even within the same product line, you can see CJ-4 lubes with a TBN of 7, while others exceed 10, depending upon which ACEA specifications are claimed.
This reminds me of my old ford truck f100. I left the same oil in for over 5 years...it is still running today, yes I did change it when I sold it..go figure..
Originally Posted By: bigt61
Originally Posted By: dnewton3
YES - It's CYA. It's about covering their posterior in regard to warranty.
OCIs are your cost. Warranty claims are their cost.
Doing the math is easy; they write a policy that places the burden of cost upon you and reduces the risk of warranty claims to them.
+1 They also assume(usually correctly) that no one ever checks their oil level. What's worse - 1 or 2 qts low on conventional after 5k miles.....or 3-4 qts low on synthetic after 10k miles? Chevy increased the sump capacity in their new trucks for the sole reason that people don't check their oil.
I check my oil once the little red lamp light comes on!
Originally Posted By: dnewton3
YES - It's CYA. It's about covering their posterior in regard to warranty.
OCIs are your cost. Warranty claims are their cost.
Doing the math is easy; they write a policy that places the burden of cost upon you and reduces the risk of warranty claims to them.
+1 They also assume(usually correctly) that no one ever checks their oil level. What's worse - 1 or 2 qts low on conventional after 5k miles.....or 3-4 qts low on synthetic after 10k miles? Chevy increased the sump capacity in their new trucks for the sole reason that people don't check their oil.
I check my oil once the little red lamp light comes on!
More CYA, Don't forget contamination including from an external source. If used in a continuous dusty environment changing it more frequently may be necessary. And if analysis are not being done you don't know the status of the oil. In this example extending the oil change with synthetic may be detrimental to the engine.
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