I've ran rotella syn for the last year and a half and was very pleased overall with it as far as cold starts here in MI and it also felt like it gave me a little extra power. Now, since its $19 a gallon, I decided to go back to rotella 15 w40 dino. I changed the oil, ran my truck for 5 min and shutdown.
I was quite disapointed when my truck rolled over slow on a 10 degree morning and stalled once and then proceeded with about a 15 seconds of romp, romp, romp... with a little rough idle and finally cleared up after a few minutes. Is this oil related or is there something else causing this issue? I really don't ever remember my truck doing that even with 20 below zero. it was 35 degrees this morning and it did the same thing only not near as bad.

 

most likely oil related. That's why most people switch to synthetic.

 

If you take rotella 15w40 and syn rotella 5w40 and put them outside in the container in cold weather.. the 15w40 will be thick like molasses.. For the few dollars you are saving, i would suggest that you stick with the syn... your engine/injectors will love you forever..! (you can extend your oil changes with syn to compensate for the extra cost..)

 

I feel like draining the oil out and putting the synth back in. even though its 19/gal.

 

Try and plug the block heater in for a couple to 3 hours befroe you start it when you know that it isgoing to be cold. I bet the romps go away. I get Rotella Syn at Walmart. I agree that it is more expensive but you can go a bit longer on the oil changes also. To me it is worth it because of the quiter running to the engine and also the dissaperance of the romps.

 

No question that it is oil related but why?

I am beginning to lean towards a dirty/worn IPR. The cold thick dino causes it to stick or react slow causing a rapid overfuel/underfuel pulsation ie "the romps". Once the needle in the IPR positions itself correctly, things settle down.



Disclaimer: "But I could be wrong"

 

how do i test a ipr? I know they arn't cheap units.

 

15w40 dino is what i run. Never had romps. untill recently and found out that i had two dead glow plugs. And later on my relay stopped working(again for the seond time). In the middle of replacing both now. Hoping to cure the romps. I will also switch to SYN on the next change. Curious also about the IPR testing and Guzzles input. Interesting.

 

Curious if anyone knows what exactly causes the 'romp romp' on start up? Is there any damage or excessive wear occuring when this happens?

I just change my oil yesterday (15w-40 Delo 400), and this morning it did the 'romp romp' thing again.........and it was 65 degrees outside! Nothing a tap on the pedal doesn't stop, but I am concerned if it causes any harm.

By the way, Costco has the 6 gallon Delo for $52 right now.

 

I put Delo in ONCE because I heard it was good, but I got romps at 35-40°. Dumped it early and went back to syn Rotella. Won't do that again...