New problem

[Sport91]

With the truck not in gear it will rev to its hearts content, put it in gear and when it gets around 2200-2500 rpm it seems to retard itself and quits pulling. I can get up to whatever speed I need without and slipage or what I would think would be transmission/tc problems.

Also if it were transmission related I would think i could get the RPMs up put it would be slipping, this isnt the case. It just seems to hit a brick wall right after 2000, takes off just the same from a dead stop though, then hits the barrier.

any ideas?

[foggy]

do you still have cats on the truck? If so they may be clogged.

[COWL327]

+1 on the cats....i destroyed a 4l60 because of clogged cats.....

[Sport91]

I will look into that, if they are clogged wont they cause the exhaust manifolds to heatup more than usual also? Last vehicle I had a cat clog on the headers were cherry red.

[ff_jeff]

+1 on the cats... just unbolt the headers from the y pipe and drive it arround the block... You will be able to tell before you spend any money. IMO get cats deleted.

[Sport91]

If I do the cat delete it will cause a check engine light, but that can be turned off with tune correct?

What most muffler places policy on that, if it comes in without cats on it they can pipe it without cats?

[foggy]

You will need the rear O2's turned off in the tune.
You will have to cut out the cat and weld a pipe in yourself if you go this route, muffler shops will not do this.

[Sport91]

meh. my welding ability looks like cat turds


Opinions on high flow cats?

[foggy]

how many miles on your truck?

[Sport91]

125k+, probably good time for timing chain to go out too.....