[bigred1]

I just replaced the turbo 400 on my 1990 chevy 1/2 ton for the 2nd time in 2 years. Whats wrong with this picture? It cost me $1400 2 years ago and now here I go again ($1000 this time). The shop said that it is not uncommon for this to happen. This time I am having them add a shift kit. I tried to have this done last time and they discouraged me. They will "stand behind it" for 6 mos or 6000 miles.

Did I get screwed?

 

[wyldman]

That is pretty steep.Most 400's here go for about $4-600 inc a rebuilt convertor.They also last forever,so I would assume that there may be something else wrong,or the guy doesn't have a clue what he's doing.

Make sure they are flushing the cooler and lines,so the new trans doesn't get contaminated.You are running a big cooler right ? The shift kit will help too.

 

[bigred1]

400 t

yes I am running a cooler, how big? I didn't know they had sizes.

 

[wyldman]

They are usually rated in GVWR sizes.

Anything bigger than 6X8" should be big enough.

 

[TLS]

I wasn't aware you could get a TH-400 in a K1500? Wasn't it the TH-350 for small blocks under 8600 GVW? And the 700-R4 as an option?

Anyways, thats not important, what is, is that your going through Trannies like Grant went through Richmond.

You should be running a standard radiatior tank cooler and a LARGE stand alone cooler up in front.

Maybe you have a pinched cooler line, or like wyldman said, maybe they aren't being all that carefull with contaminants during assmebly.

You do have full automatic operation (kickdown for passing gear or kickdown to 1st, right?)

They're great trannies, but you have to keep them clean and cool.

In a 1500 with only a small block, you should be going forever with a TH-400!

Something is wrong.

 

[wyldman]

They never used the TH 350's in the newer trucks with 3 speed autos,only the TH400.

 

[bigred1]

Thank you for your input. BTW, it's a 4.3 liter V6 motor. Can you elaborate on the underhood cooler? Also, could you elaborate on your question about a full automatic operation?

 

[TLS]

WOW, that tranny SHOULD last FOREVER with a V-6 pushing it!

Anyway.....

Full automatic is if you are say driving at 55 mph and stomp down on the throttle. The trans should kick down to 2nd gear, and (with the V-6, slowly) GO. Same as if your doing 25 mph and are in 3rd, you stomp on it and it sould go down to 1st.

As for the coolers.....Next to your battery you should have two silver hard lines going into the side of your radiator tank. If all they do is this go in and back out to the transmission, then you haven't got a aux trans cooler. Believe it or not, my Big Block K3500 came just that way! No external cooler. I have the HD towing package and all! Anyway, if it has an aux cooler it will go from that radiator tank internal cooler to an external cooler out in FRONT of the radiator behind the grill. It will be about the size of a sheet of paper.

If you DON'T have one, then you NEED one to plow with, as if your engine coolant overheats, it will also not cool the tranny as well.