So after I started driving the car agian a lt1 backed to a 4l60 e @ 107k mods include cc503 cam 1.6 roller rockers a pair of shorty headers and a 52 mm Arizona and speed intake as far as I know I got the car off Craigslist back last year in July but ran into some what I believe to be trans issues the car had a wild sounding grinding noise coming from the trans and would like to hold shifts cold or hot, when on the throttle half way or more maybe less than half it would not like to shift into 3rd or 4th easy it would either buck real hard or hold the shift for a couple seconds or until you let off the gas a bit. the car also has 4.10 gears in the back on some mt et street ss 255 60 15 it would hold 3rd and 4th gear shifts till about 3-4 k rpm at about 50-60 mph for 3rd and 100-110 in 4th when trying to get up to speed .another thing which I think could be the converter or something else if you would go more than half throttle or so the engine would just jump rpms rev to the rpm it’s trying to obtain but it would almost feel as if the trans took a second to catch and go almost like a car building boost on a pull ( metaphorically speaking )
i recently changed out the tranny fluid and put a quart of Lucas tranny non slip the grinding noise seems to have gone away if not been muzzled down so much you can’t really hear it the car seems to be shifting and catching all gears like it should driving normally around town but when I would go to make a pull from the dig first would shift great and so would second but 3rd is where I would have the problem where it felt like my trans couldn’t keep up with the jump of rpm or change of gear then I would let of the throttle till I felt it catch then give it 100% throttle and it would go as if it was working great all the way threw the rest of 3rd. until 4th then the same thing but happens But Doesnt take as long to catch.

If anyone needs a better description on what is going on I would be more than happy to try and explain thank you

 

Any DTC trouble codes? Check Engine Light trouble code such as P1870 for transmission component slippage? My guess would be that the 3-4 gear clutches are fried and laying in the bottom of the pan. Time for a rebuild if this is the problem though you should still have 1st gear, 2nd gear and reverse. And it is safe to drive it in manually shifted 2nd gear IF THIS IS THE ONLY PROBLEM. However, the grinding noises you mention indicate that you have other problems and you may be further damaging some expensive hard parts inside your trans.

I'd get it towed to a shop or drop the trans yourself and take it to a shop. And look for a repair place with a transmission dynamometer so that your rebuilt trans can get tested (pressures, shifting and any codes) before it goes back in. A shop local to me has a dynamometer and I will be needing it very soon. Why? Because my 4L60E, at 150,000 miles, has the same problem as yours minus the grinding noises.

Rick

 

My check engine light comes on and off as most do but I’ve never gotten around to actually getting a obd1 scanner and seeing what codes the car with throw me but thanks I’ve gotten a quote at 1600 but they want to throw a 2000-2200 stall coverter I think that’s a bit to low but I don’t know much on transmissions

 

Well if it was not already time to take the transmission apart...

Now that you have put that Lucas stop slip/ stop leak garbage in the transmission, it is definitely time to take the transmission apart!

Good luck with the rebuild, hopefully just the paper/ rubber/ seals and the clutch/ steel module will get you 90% back together and the last 10% in simple improvements/ design changes to improve and modernize the transmission.

 

I would not go less than a 3200 stall speed converter.

 

Appreciate the help guy I went to the track and went 8th mile racing since the higher gears don’t seem to catch still ran a 7.9 @ 81 with a 1.97 60 foot I think it is Time for that rebuild considering I was cracking into 12s the points to get lower not higher time right lol but agian thanks