• Welcome to The Truck Stop! We see you haven't REGISTERED yet.

    Your truck knowledge is missing!
    • Registration is FREE , all we need is your birthday and email. (We don't share ANY data with ANYONE)
    • We have tons of knowledge here for your diesel truck!
    • Post your own topics and reply to existing threads to help others out!
    • NO ADS! The site is fully functional and ad free!

    Problems registering? Click here to contact us!

    Already registered, but need a PASSWORD RESET? CLICK HERE TO RESET YOUR PASSWORD!

Oil cooler leak


New Member
Reaction score
New York
Working on my sons 06 LBZ. It has a coolant leak where the oil cooler elbow meets the block. He took it apart and somehow got the whol assembly out but now we can’t get it back in. The elbow on the back of the oil cooler hits what I believe is called the midplate before the holes line up on the block for the two o ringed oil passages. I don’t see how this happended as it was in there but I have tried everything. If I take the elbow off , the oil cooler goes right in. It almost seems as if I have to grind out the midplate to give it clearance but it came apart. We have been trying for 4 hours and cant get it back in, we tried leaving the bolts loose on the elbow. It almost seems to me like the transmission will have to come out and that midplate be loosened then the oil cooler installed while thats loose ?.
Banks had some instructions written for their l5p cooler upgrade. I just did this on an lbz in a 91 square body suburban. It’s a tight fit but it works. Does yours have studs on the bell housing side? Or is it bolts? Ours had studs so it was helpful to get the elbow up and very loosely held up by putting the nuts on the studs. Then work the cooler in and get the bolts in for the cooler side. my friends skinny fingers were helpful.

Here's the banks instructions.. not sure how helpful they'll be. but I did reference them on an off while doing this job.