Running rich and/or blown plenum, valve seals, etc. Anything that puts oil into combustion cylinder.

 

yea im loosing oil from my pan its all down the front side of my tranny and filthy under the the whole truck theres alot of buildup as well when i did my timing chain i found that there was a tear in my oil pan gasket im betting that theres another bad part of the oil pan gasket by the tranny. from time to time i have what seems to be a tranny issue its small though cuz like when im going up hills my truck shifts and goes up the hill fine. is there a possibility that the connectors have build up of old and new oil crap so the connection isnt the greatest??? thus causing what seems to be the begining of a slipping tranny?

 

Have you looked at tranny fluid? Look clear or dark brown. May need to change filter and fluid (ATF+4 only) and no additives. Check band adjustment (inch pound torque wrench) and possibly clean governor solenoid and pressure sensor.. That may do it.

 

fluid seems fine did a filter change like two months ago. next time i go in im going to do bands and solenoid. however it doesnt seem like its slipping. its got power up hills it shifts about 2800 rpms to 3000 rpms its just once in a while it will take a second longer to shift in. also from time to time when i accelerate it will shift into gear and rpms will come back down but than a second later it seems to adj again than just be alright.

 

You might look at adjusting TV cable. It is on the side of throttle body, and instructions are near the beginning of the trans section in the FSM. That will effect shift points.

 

Ive thought about that abd I truly believe thats playing a role because my gas peddle is very touching little bit of pressure and it does alright too much at one time and it does nothing but rev higher than normal

 

When I was young(er) and dumb(er) I gutted the cat in my Bronco II (no reason, it wasn't clogged) and hated the sound. No cat sounded way better but was way too loud after a while, I installed a cat again and was happy overall. Never noticed any performance difference in any of the setups.



And as has been said before, backpressure is not good, it's only bad (for a 4 stroke anyways). When people attribute a loss in backpressure to a loss in performance what's actually going on is decreased velocity/scavenging and increased turbulence, which actually causes an increase in backpressure and inhibits performance. Either way, for the most part, none of this has much real world affect on the majority of our engines.

 

So which is better-

Gut the cat and reinstall the housing or,

Remove the cat and install a section of straight pipe, weld in a bung, and replace the forward 02 sensor.

 

Oh, my bad- $156 plus tax.

It's still more than I'm wanting to spend to save the whales at this point, and honestly I don't have easy access to a welder or a lift.

 

dude i see high flow cats online for 89 to 92 bucks all the time brand new try your google dont need a welder thats what exaust clamps are for