Valve cover gasket change pics. Any concerns with the condition of these internals?

jlaw904 · Mar 15, 2021

Just changed at ~189k miles on my 2008 4.0L. It looks like there was a little more build up than I expected. How does this compare to you guys who have seen the internals for your engines? It runs fine, but I still contemplated using a bit of Seafoam in the oil right before the next change. But I'm a bit scared to after reading some of the mixed reviews on high mileage vehicles. I really don't have much history on the vehicle but have performed an oil change twice every 5k miles since I got it.

triethylborane · Mar 15, 2021

Id pass on the seafoam and keep your oil changes on the 5k mile interval.

Run your finger over the cam lobes, do you feel any ridges? Have you checked valve lash with a feeler gauge for within specs? Timing/variable system chains within stretch spec? All gaskets pliable?

Those are the items I would focus on with the valve covers off. The oil deposits that are cooked on are typical, its going to happen and getting rid of it isnt critical.

Drcoffee · Mar 15, 2021

Marvel mystery oil is less aggressive than seafoam. Add a quart to your oil each time you change the oil. After two changes you will see a clean motor. I add 1/2 Qt MMO to each oil change to keep internal part clean.

gimlithepirate · Mar 15, 2021

jlaw904 said:
Just changed at ~189k miles on my 2008 4.0L. It looks like there was a little more build up than I expected. How does this compare to you guys who have seen the internals for your engines? It runs fine, but I still contemplated using a bit of Seafoam in the oil right before the next change. But I'm a bit scared to after reading some of the mixed reviews on high mileage vehicles. I really don't have much history on the vehicle but have performed an oil change twice every 5k miles since I got it.

I just did mine, and my cover looked similar, but there wasn't as much gold color in and around the cams as there are in your pictures.

From other comments sounds like Marvel Mystery oil might be worth grabbing a bottle to run half through the oil and half through the engine.

BlackWorksInc · Mar 16, 2021

Doesn't look that bad honestly, a bit of some heavy varnish build-up; but hardly any sludge chunks or gunk. Looks like a 180k Toyota engine to be honest. I think MMO might help with some of the varnish, or going with something like 3-5k oil changes.

I have seen far worse out of these V6s at far less mileage before I'd get concerned.

delucat2 · Mar 16, 2021

not terrible

my 2003 v8 with 245,000 looked a bit better, but not too much. 2nd owner (bought with 80,000, me with 165,000) and I have don'e synthetic at 5,000 miles. I wouldn't try to clean, just reduce interval. oil is cheap.

Valve cover gasket change pics. Any concerns with the condition of these internals?

jlaw904

Member

triethylborane

Member

Drcoffee

Senior Member

gimlithepirate

New member

BlackWorksInc

New member

delucat2

New member

Similar threads

Members online

Forum statistics

Share this page

Trending content