Late shift, rev into reverse!?

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

WayneJ

Newbie
Joined
May 27, 2016
Messages
40
Reaction score
3
Location
California
Good afternoon gmt junkies. I have a problem and could use some expertise. I just put a used 5.7 into a k1500. I bought it with a blown motor. Has a rebuilt tranny though for sure. Previous owner said its been replaced this year and when I dropped the motor there wasn't a spec of dust inside the bell housing. However I just got it up and running and it doesn't want to shift when under throttle but has no problem doing So at just over idle. When input it in reverse I have to give it about 2000rpm before it moves backwards. And if I give it WOT in overdrive there's a vibration through the floor and a metal on metal rubbing noise. I put in a new tps so I know that's not the issues. Any help please and thank you!!
 

Jrgunn5150

Enjoying tomorrow's success today
Joined
Aug 23, 2014
Messages
5,847
Reaction score
1,283
Location
Ionia Michigan
You might have a VSS issue, or a sun gear failure.

Does it shift fine manually and at part throttle?
 

WayneJ

Newbie
Joined
May 27, 2016
Messages
40
Reaction score
3
Location
California
I haven't tried to shift through the low gears yet. What is vss? Also when I rev the engine in neutral the speedo will move even if in in park
 

WayneJ

Newbie
Joined
May 27, 2016
Messages
40
Reaction score
3
Location
California
Vehicle Speed Sensor. Seems to be likely.
Ok cool I'll see if I can't go grab one. However I also noticed that when I first put it into drive from reverse nothing happened. I had to put it in park then back in drive for it to do anything. Also when I start it up it will put and sputter for about 10 seconds. Then it will rev up to 2000rpm and settle back down to idle.
 

Jrgunn5150

Enjoying tomorrow's success today
Joined
Aug 23, 2014
Messages
5,847
Reaction score
1,283
Location
Ionia Michigan
Ok cool I'll see if I can't go grab one. However I also noticed that when I first put it into drive from reverse nothing happened. I had to put it in park then back in drive for it to do anything. Also when I start it up it will put and sputter for about 10 seconds. Then it will rev up to 2000rpm and settle back down to idle.

At a guess, i'm going to say you have some unrelated issues going on. The sputtering and reving at idle sounds like a dirty TB, or IAC
 

WayneJ

Newbie
Joined
May 27, 2016
Messages
40
Reaction score
3
Location
California
I just took it for another test drive and it seems that when I first start up or when it's cold it will shift perfect. However once it warms up its almost sounds like it has to clutch. So I'll rev the gas going like 20 or 30 and it will sound like I'm letting the clutch out real slow and it'll catch and slowly speed up. At the same time it randomly makes that loud metal on metal sound.
 
Top