RayRob65

I had a 1990 GMC 4X4 work truck that would lock up and finally had to replace the locking differential unit in it.

This is a long story, but I will tell it as fast as possible. I bought a 1995 GMC Seirra SLT K1500 Z-71 a few years back with a weak motor that smoked. It is a very clean rust-free truck. It sat beside my house for 2 years with me occasionally starting it up. I decided to find a good used engine for it which I did. I found a very good running 5.7 for it that I heard run before it being pulled. It had great oil pressure, no knocks or pings and no smoke at all after messing with it for about an hour revving it up, brake torquing it lightly, steady 2000-2500 RPM rev, the whole 9 yards, so I bought it. I got hurt at work and couldn't put it in myself, so I found a (supposedly) good shop to put it in. The engine sit in the back of the truck, fully wrapped up, for about 2 months before I found this shop. So, I dropped the truck off there on March 14 of this year and told the shop that I wanted for them to put a new tranny seal, rear main seal, oil pan and valve cover gaskets on it when they installed it and check the A/C out because it wasn't cooling. They said it wouldn't be a problem, but it would be about 4-6 weeks before they could get to it and gave me an estimate of $1200-$1500, which I said was fine. On May 20 (9 weeks later) I called to check on it and he said it was next in line but his mechanic was taking a few days off that week and he couldn't start on it until the end of next week (May 26 or 27- Memorial day weekend). That had me pretty upset but what could I do, so I asked when he thought it might be ready and he said 2-3 weeks!!! That really got me mad, but I didn't get irate, I just said wow, well OK, call me just as soon as he got it done. So finally on June 17 they call and tell me it was ready, so my wife and I head over to get it. When we got there they didn't have my bill ready and it would be a little while before his wife could finish it because it was so long,?????. After waiting for around 45 minutes she said it was ready and I walked up to the counter to pay it, expecting to pay around $1500. NO, the bill was a little over $3000!!! I questioned it and she handed me the itemized bill. He had put all new gaskets on it, even pulled the heads and put on new head gaskets(voiding the warranty that I had on the engine). Charged me $675 labor to put on the head gaskets, that I didn't want done in the first place and I furnished the gaskets I wanted changed. He basically went through the whole truck and supposedly fixed everything totaling up to almost $2300 labor alone. I asked them why the extra work was done and she said that's what had to be done so I just angrily paid the bill and took my truck. Now for the real problem. On the way home, I noticed the truck smoking and the air was still not cooling. I called them and told them what was up and he said there was oil in the exhaust and to drive it around for about a week to see if it would clear up. I also told him that the air was not working and that the Schrader valve on the high side was blown because it was hissing through the cap. he said that it must have happened on my way home and when I could bring it back over in about a week and he would fix the air again, after spending $200 to get it fixed the first time, it would be about another $100, and he would see about the smoking problem then, if it's still smoking. It has been a week today and it's still smoking. What I am asking is, if there is oil in the exhaust, how long would it take to burn out? If it's not that, then what could be the cause of a great running engine start smoking just from being swapped in and head gaskets put on it? Also, where is the 02 sensor on these trucks? I swear the old engine had it on the driver's side manifold, but now it's just got an old rusty, broken off one in it and can't find the plug for it!? It's been a nightmare but I really like the truck because of how clean it is. Any and all help is appreciated.