2010 Kubota 900 RTV hard starting when cold

[Fastfords]

My Kubota is very hard to start in cold weather. I thought it may be the battery or alt. but both tested great.
I have to cycle the glow plugs for about 45 seconds or so 3 or 4 times for it to even try and start. It's very slow turning over. Most times it will start but it is very hard to get going.
In warm weather I am good to go, starts up with no issues.
Looking for some help figuring out what is gong on.
Thank you

 

[Roadworthy]

A lighter oil may help cold weather starts. If you've load tested the battery clean connectors and cable ends reinstalling TIGHTLY. Look carefully for signs of corrosion around the connectors. Clean and tighten ground contact at frame.

 

[Williy]

When I lived in Wisconsin I used 10W30 syn oil in my truck and
car and never had a problem with starting
Here we seldom see any freezing weather I use 15W40 and
even when the temp drops below freeZing I still have no problems
Have you checked your glow plugs?

willy