[Rusty Nib]

Hey Guys -
I need to replace my 02 sensors. I have 2. One upstream. One downstream. The dealer ran my vin and insists I have 4. All the parts stores only have a listing for 4.

A friend with an 05 says he saw a notation in his factory shop manual about the early 03's with the 5.7 having only two 02 sensors but quickly changing to 4. I have not seen this with my own eyes, but figured you guys could vouch for that.

My question is simple: Are the part numbers for the two O2 sensors I have the SAME as the part numbers for the Rams with 4 sensors?

Thanks for any help you can offer. Anyone who doubts my sanity is welcome to crawl around looking for the other two sensors. You wouldn't be the first to try... and fail.:gy:

 

[snrusnak]

Well I'll be the first idiot to question you lol! You MUST have at least two upstream sensors, one for each cylinder bank. If you only have one upstream and one downstream, then something is wrong. I guess technically they could have designed it to ignore one cylinder bank, but I've never seen a setup like this and would expect it to operate not so great. IF you truly only have the two, I'd bet they are the same part numbers as the newer design...I'd certainly take another look though...or two or three more looks lol

 

[09nitetrain]

alot of non cali. emission dodge truck/suv products will only have two. one in front of the convertor and one behind it. check your emission tag under the hood it will say something like this( vechical is us epa cali. and federal emission....... but if there is no mention of cali. then you might just have two. but also check your manifolds cause sometimes they will stick them right before the flange and then right after the convertor. i hope this helps

 

[FrostKing]

Your '03 most certainly has only 2 sensors, one in the y-pipe and one after the single cat. converter. It seems to me the style of sensor also changed after '03, so let me get back to you.

 

[snrusnak]

After reading the other posts and thinking some more, you could have one sensor where the down pipes merge then one after the cat...that would make sense.

 

[FrostKing]

The '03s have a 4-wire Zirconia sensor with a signal of 0.1 to 0.9 volts. I believe the newer trucks use the Titania 4-wire sensors that are 0-5 volts.

 

[Rusty Nib]

You guys are FANTASTIC! Thank you Frost King! This means I'm not crazy!!!!

Any idea how I could find the right (0.1 - 0.9) volt Zirconia sensors? I want to make sure I order the right ones seeing as how you can't return electronic parts and all.

Thank you again!

 

[snrusnak]

Any idea how I could find the right (0.1 - 0.9) volt Zirconia sensors? I want to make sure I order the right ones seeing as how you can't return electronic parts and all.

Easiest way to ensure you get the right one(if you can't find it online or in their manual) is to take it with you to autozone and have them match it up. What makes you think it's bad anyway? Even if the upstream needs replaced, there's no need to replace the downstream, it should only be monitoring catalytic efficiency, not adjusting air/fuel ratios. Unless you have emissions inspections it won't matter, but could also indicate a bad/clogged catalytic converter. Do you have an engine light and what is the code? And you can return O2 sensors as long as they weren't installed.

 

[Rusty Nib]

Good to know, thank you. I don't remember the code off the top of my head but will get back to you. I hadn't considered the catalyst being the culprit...

 

[snrusnak]

yeah if the code is for upstream sensor then replace it. If the code is for downstream sensor then either the sensor is bad (doesn't really matter) or the catalytic converter is bad/clogged (should replace or fix). How many miles on the truck?