Us­ing the low­er-rat­ed fu­el over time can some­times cause pre­ma­ture en­gine wear and en­gine fail­ure, ac­cord­ing to Neal and Massy Au­to­mo­tive Ltd. How­ev­er, State-owned Na­tion­al Pe­tro­le­um is­sued a state­ment that says oth­er­wise: "Mov­ing from pre­mi­um to su­per in an en­gine with an oc­tane rat­ing of 92 or less should not cause dam­age to the en­gine, clog fu­el in­jec­tors, add to main­te­nance costs or lead to an ab­nor­mal car­bon build-up."

The oc­tane re­quire­ment of an en­gine in­di­cates the type of fu­el that should be used. The is­sue of what kinds of ve­hi­cles should use pre­mi­um or su­per gaso­line has arisen since Fi­nance Min­is­ter Lar­ry Howai stat­ed in Mon­day's bud­get that the price of pre­mi­um fu­el went up from Oc­to­ber 1 from $4 a litre to $5.75 a litre, as part of Gov­ern­ment's plan to re­duce the fu­el sub­sidy.

In a joint full-page ad­ver­tise­ment in yes­ter­day's news­pa­per, Neal and Massy Au­to­mo­tive and Best Au­to Ltd iden­ti­fied 53 ve­hi­cle mod­els and what type of fu­el they can use. Of the lot, 24 of the ve­hi­cles can use su­per. For in­stance, man­u­fac­tur­ers rec­om­mend that the Hyundai Ac­cent, Nis­san Ce­firo and the Vol­vo S40 can use su­per, while the Nis­san Teana 3.5L, the Peu­geot 407, the Sub­aru Foester, the Volk­swa­gen Pas­sat CC and the Vol­vo C30 can use pre­mi­um.

Neal and Massy Au­to­mo­tive said mo­torists should use what­ev­er re­search oc­tane num­ber, known as RON, is rec­om­mend­ed by man­u­fac­tur­ers, to pre­serve the life and per­for­mance of their en­gines. "In some in­stances, us­ing the low­er-rat­ed fu­el over time can re­sult in pre­ma­ture en­gine wear and en­gine fail­ure. The use of oc­tane boost ad­di­tives is al­so not rec­om­mend­ed over ex­tend­ed pe­ri­ods," reads the Neal and Massy Au­to­mo­tive ad­ver­tise­ment.

NP stat­ed that a ve­hi­cle re­quir­ing a min­i­mum oc­tane rat­ing of 91 "can" safe­ly use su­per, which has a RON of 92 min­i­mum. A ve­hi­cle that needs a min­i­mum oc­tane read­ing of 93 min­i­mum "needs" to use pre­mi­um, which has a RON of 95 min­i­mum and NOT su­per.

NP makes the point in its state­ment that all the gaso­line fu­els it mar­kets, in­clud­ing su­per, are un­lead­ed. Both Neal and Massy Au­to­mo­tive and NP said mo­torists should use the oc­tane read­ing rec­om­mend­ed by man­u­fac­tur­ers.

Ve­hi­cles rec­om­mend­ed to use pre­mi­um:

Nis­san: Ce­firo, Juke 1.6MT Tur­bo, Ti­i­da, X-Trail 2.0 Clas­sic

Vol­vo C30, S40, S60, S80, XC60, XC90

Peu­geot:?206, 207, 307, 308, 407

Sub­aru: Forester, Im­preza, Lega­cy, Tribeca, XV

Volk­swa­gen: Jet­ta 1.4L, Golf Vari­ant 1.4L, Pas­sat 2.0, Pas­sat CC, Tiguan

Ve­hi­cles rec­om­mend­ed for su­per use:

Nis­san: Almera, March, Syl­phy, Sen­tra, Wingroad, X-Trail 2.5L

Volk­swa­gen: Bo­ra, Golf Vari­ant 1.6L, Jet­ta 1.6L/2.0L, Pas­sat 1.8 and Po­lo