- May 17, 2001
The guy I bought my 98 XR400 from used HP4. At my local shop, it runs $7 a quart. What is the difference between HP4 and GN4? I did a search, but couldn't find any info already posted except someone saying use GN4, HP4's too expensive. Is the HP4 that good? I'm not trying to be cheap, but I don't want to waste my money buying it if there's no need to.