Hi guys,

Sorry if this has been done to death (I looked in the stickies etc..) but I am wondering if I should be using Synthetic in my 2003 Heritage Softail. This is a new-to-me bike as of this year but was always using convential HD oil before. Bike has 80,000 KMs on it (~50k Miles). Should I use Synthetic or do I risk starting a leak? I've always heard that you should not use Synthetic oils on older cars as you might suddenly find a leak that didn't exist before, so don't want to risk it on my bike. I use my bike as a daily driver so often in heavy traffic in the hot sun in the summer, so worried about heat.

Thanks in advance,
Dan

 

So the bike has 50,000 miles using conventional oil. What does that tell you????????

 

Honestly, it doesn't tell me anything. It could mean it's fine just keep doing what you're doing what's always been done. Or it could mean this is a higher mileage bike, it's time to really protect it and use Synthetic. So yeah, not helping clear anything up lol

 

Go to synthetic Dan.

Seals won't be an issue in a 2003 machine with todays synthetics and the characteristics of a synthetic make it particularly valuable during Canadian (cool morning) startup / warmup periods. If you don't mind paying $$ and are still concerned about seals, use Red Line. It is only unique in that it uses an Ester base vs the more common PAO bases and if anything, causes seals to swell.

That said,, all synthetics, and ester based ones in particular, are naturally "high detergent". If long term use of bargain, waxy, dino oils has resulted in a lot of engine lacquer buildup, synthetics will rapidly dissolve this when you switch. Problems related to that may occur.

If I were in your shoes, I'd do the switch and bite the bullet on an early post switch oil/filter change, just to see whats going on. I would not switch to a synthetic with the intent of extending change intervals going forward. Continue to change per schedule.

If you switch and don't like the result, just switch back. There are no issues or special procedures with switching between dino's and synthetics, either way.

 

Great information, thank you!

 

If it is running fine then why?

 

Just because it's running fine so far on conventional doesn't mean that trend will continue or that switching to synthetic would further protect from damage on an older engine.

 

You are flogging a dead horse here! Your bike (and all of mine throughout the last 50 years and over half a million miles) have done fine on normal oils. You will gain nothing IMHO in swapping over to synth in your bike, except for paying a bigger invoice. Your engine will not last any longer or perform any better. However the final choice plainly remains with you.