When to Switch from Break-In Oil to Conventional Oil
When to Switch from Break-In Oil to Conventional Oil I am pretty close to finishing up a build (cast iron 346, forged bottom end, HCI). I won't have a tune to begin with and my tuner is 6 miles away. I plan to use engine break-in oil for the initial start-up and am wondering at what point do you guys change it out to conventional oil. After start-up and checking for leaks, low to medium revs...
Should I keep the break-in oil and change it out to conventional after the dyno pulls?
Or change out the break-in oil to conventional oil after initial start-up/revving but before heading to the dyno?
Should I keep the break-in oil and change it out to conventional after the dyno pulls?
Or change out the break-in oil to conventional oil after initial start-up/revving but before heading to the dyno?
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Truckdoug hit on an important point; getting the assembly lube flushed out along with any metal particles, AND changing the filter SOON to get rid of it. Use dino oil to do that, only because it's cheap and you're gonna change the oil a few times with very short intervals to achieve the above.
So first change oil AND filter after first warmup and heat cycle, then maybe 100-200 miles later, then 500. After that use whatever synthetic you use and go a full interval.
So first change oil AND filter after first warmup and heat cycle, then maybe 100-200 miles later, then 500. After that use whatever synthetic you use and go a full interval.
Everyone has their opinion on what oil to use and what not to use during break-in. A lot of people say not to use synthetic blend or full syenthic oil for breaking-in an LS engine, but to use something like Valvoline VR-1 or Joe Gibbs break in oil. So is GM wrong for running 5w30 dexos Gen 1 or 2 for factory filled brand new engines that come right off the assembly line? Gen 1 is a synthetic blend and Gen 2 is full synthetic.
I switched from break in oil to regular oil before I filled the engine for first start. Like truck Doug said, almost exactly.
Start it, let it run in but keep rpm moving around, let it warm up, take it out and do 2000-5000-2000 rpm pulls in second, but don't clutch in on decel. Load the rings up. About 15 pulls, go home, change oil and filter.
Start it, let it run in but keep rpm moving around, let it warm up, take it out and do 2000-5000-2000 rpm pulls in second, but don't clutch in on decel. Load the rings up. About 15 pulls, go home, change oil and filter.
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I switched from break in oil to regular oil before I filled the engine for first start. Like truck Doug said, almost exactly.
Start it, let it run in but keep rpm moving around, let it warm up, take it out and do 2000-5000-2000 rpm pulls in second, but don't clutch in on decel. Load the rings up. About 15 pulls, go home, change oil and filter.
Start it, let it run in but keep rpm moving around, let it warm up, take it out and do 2000-5000-2000 rpm pulls in second, but don't clutch in on decel. Load the rings up. About 15 pulls, go home, change oil and filter.
Getting it out and doing the 2000 to 5000 back to 2000 as Darth has said is essential to seat the rings. This loads and unloads the rings in a quick cycle, which aids in ring seating. This is the most important step in my opinion, to engine run-in.
Whatever you do, do not lug a newly built engine. Keep rpm well above idle, while driving, for the first 15 minutes. This keeps oil where it’s needed, in the crucial break in period.
Last edited by Che70velle; Nov 6, 2018 at 08:58 PM. Reason: smellcheck...
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I did the same as darth stated on my L76 rebuild, I only went to 4500 though. For the first 100 miles I kept doing it and never stayed at a certain RPM and was always above 2000. I did use some comp cams break in oil additive though for the first 3 changes (its cheap so I thought why not). Changed filter and oil after first start/drive with loading, 50 miles total and was monitoring oil pressure. Then another change at 500 miles (still with additive) and then another change at 1500 (still with additive). At 1500 I switched to delco semi synthetic because I go it on a super sale ($2.25 a quart). I'll probably go back to the shell dino GF5 I used for break in though on the next change since its only $2.4 a quart.
I switched from break in oil to regular oil before I filled the engine for first start. Like truck Doug said, almost exactly.
Start it, let it run in but keep rpm moving around, let it warm up, take it out and do 2000-5000-2000 rpm pulls in second, but don't clutch in on decel. Load the rings up. About 15 pulls, go home, change oil and filter.
Start it, let it run in but keep rpm moving around, let it warm up, take it out and do 2000-5000-2000 rpm pulls in second, but don't clutch in on decel. Load the rings up. About 15 pulls, go home, change oil and filter.
Everyone has their opinion on what oil to use and what not to use during break-in. A lot of people say not to use synthetic blend or full syenthic oil for breaking-in an LS engine, but to use something like Valvoline VR-1 or Joe Gibbs break in oil. So is GM wrong for running 5w30 dexos Gen 1 or 2 for factory filled brand new engines that come right off the assembly line? Gen 1 is a synthetic blend and Gen 2 is full synthetic.
In short, an OEM build LS1's break-in has the deck stacked in its favor and synthetic oil is perfectly suited.
A custom build LS1's break-in doesn't have the deck stacked in its favor so there is much wisdom in using a conventional oil like VR1 or other similar oil for break in. The engines are in many way a bit more similar to the engines from 30 years ago and more break-in sensitive than an OEM engine.
Let's stop and ask this question, is the typical custom build LS engine really similar as a factory built engine?
In my experience, the answer is no.
Few people rebuild to stock specs. The typical aftermarket engine will have a different ring set than factory, typically with forged pistons, more aggressive camshaft with more lift and duration and so on.
GM has their process down to an exact science. There's absolutely GM maintains very tight cost effective production tolerance with the factory parts and machining practices. Aftermarket vendors can't maintain near perfect build tolerance out of the box like an OEM auto manufacturer.
The time spend checking parts for exact tolerance is simply too costly for the aftermarket. GM controls selection of every part that goes into their engines. Basically the same type parts are used over and over in an OEM engine and held to high quality standards. Aftermarket builder is at mercy of what the customer wants with thousands of different crank, rod, piston, bearings, ring combinations possible for suppliers of various levels of quality control. There is much more of a human factor in custom aftermarket build engines than in a OEM manufactured engine.
This is amusing
Wiki on break in
"Some users will not give credence to the engineers and will stick to their own ideas anyway; but their careful break-in beliefs are still harmless and serve roughly like a placebo in allowing them to assure themselves that they've maximized the equipment's working lifespan through their due diligence. Some manufacturers have removed break-in procedures because mechanically they are no longer useful. Other manufacturers list procedures to avoid customer arguments the manual was incomplete because the procedures were missing. The useful side effect of a "break-in at slower speeds" for vehicles is operator familiarization. An overly exuberant operator crashing the new vehicle hurts people, reputation and sales."
Will the vehicle survive breaking in the new owner...
Wiki on break in
"Some users will not give credence to the engineers and will stick to their own ideas anyway; but their careful break-in beliefs are still harmless and serve roughly like a placebo in allowing them to assure themselves that they've maximized the equipment's working lifespan through their due diligence. Some manufacturers have removed break-in procedures because mechanically they are no longer useful. Other manufacturers list procedures to avoid customer arguments the manual was incomplete because the procedures were missing. The useful side effect of a "break-in at slower speeds" for vehicles is operator familiarization. An overly exuberant operator crashing the new vehicle hurts people, reputation and sales."
Will the vehicle survive breaking in the new owner...
A little confused on the first part. You switched from break in to regular before even firing it up for the first time? I thought the whole point was to put in 5.5 qts of break in oil for initial start up/revving and then switch to conventional after the first oil/filter change.
Quote of the day right there. Laughed out loud and got weird looks from co-workers.