what oil is equivalent to 424

424 is not a common oil weight. It might be an old part number for a specific brand. I'd cross reference with the owner's manual. Usually these quads take 10W-40 or 5W-40 with JASO MA rating for wet clutches. Check the manual first.

I ran 10W-40 in my LTZ400 for years without issues. But make sure it's motorcycle-specific oil for wet clutches. 424 might have been a Castrol or Yamalube number. I'd just use a good synthetic 10W-40.

Be careful just swapping oils. 424 could be a 20W-50 if it's for hotter climates. Best to look up the actual specs or contact a dealer with your VIN. Don't guess.

If you can't find the exact 424, any quality JASO MA 10W-40 should be fine for trail riding. That engine is pretty tolerant. I've used Rotella T6 5W-40 with no problems.

Actually 424 is likely a Mitsubishi or Suzuki part number for 10W-40. I've seen it on older models. Just get a good synthetic 10W-40 with wet clutch certification. You'll be fine.

Disagree with the above - the number might indicate something specific like a 5W-30 if it's a cold weather spec. Better to check the manual before switching. I've seen guys ruin clutches with wrong oil.

I use Shell Rotella T5 10W-30 in my Polaris but that's different. For your Suzuki, I'd stick with 10W-40. The 424 code probably was just an old dealer inventory number. No magic oil.

You can usually find oil specs online if you search by machine. Try looking up the OEM part number for the filter and see what oil they recommend with it. I bet it's 10W-40.

For dunes you might want a bit thicker oil in summer. I run 20W-50 in my sport quad for dunes. But if you're doing mixed trail and dunes, 10W-40 is a good compromise.

One thing nobody mentioned: make sure you don't use energy-conserving car oil. It has friction modifiers that will kill your clutch plates. Look for API SG or JASO MA on the bottle.

I have an LTZ400 and I've been using Yamalube 10W-40 for 5 years. No issues. The 424 number might be from an aftermarket oil that rebranded. It's not a standard weight.

Call a dealer and ask for the oil spec for a 2006 LTZ400. They will tell you 10W-40. Don't overthink this - any reputable brand of wet-clutch oil will work.

While 10W-40 is common, if you ride aggressively in hot weather, you might consider 20W-50. But for most people 10W-40 is fine. Change it often and you're golden.

I disagree with those saying it's definitely 10W-40. My friend's LTZ400 had a manual that specified 5W-40 for cold climates. So check your manual. The 424 could be a viscosity spec.

Honestly, I use any JASO MA2 oil I can find cheap. 10W-40 in summer, 5W-40 in winter. Never had clutch slippage. But make sure you don't mix different brands when topping off.

You can also look up the oil capacity and use a known good like Mobil 1 4T 10W-40. I'd avoid generic store brands unless they clearly state JASO MA.

Check the dipstick after an oil change warm. If the clutch feels weird or shifts hard, you might have the wrong oil. I once put car oil and had to flush it immediately.

Since you mentioned dunes, consider that sand riding heats engines more. A thicker oil like 20W-50 might be better for hot dunes, but for mixed use stay with 10W-40.

I'd order online if you can't find it locally. Many dealers stock motorcycle oil. Or get an oil change kit for your model. That way you know it's right.

Before you buy any oil, confirm the model year and any modifications. If the previous owner changed the clutch, they might have special recommendations. Ask them what they used besides the number.