What the **** am I going to do about this?

[Motorhead350]

Alright first off it's a non Marauder question, but I still need help especially from those of you who work in the auto industry. Back in November I bought a new Ram Jet 350 Crate engine for my lovely K5 Blazer. About a month later the tranny went out so I bought a new one FROM GM with a 100,000 mile warranty. Now about a month later that tranny went out and did in the same way as the last one. I took it to a dealer in my college town (different from the one that installed it) and had it fixed, but they told me it was now out of warranty because it will never work for an engine this modified. I said what are you talking about the engine is stock.... all it has is an air filter... it's a crate engine from GM with a new tranny. The place that installed the engine also did the tranny so they knew what was in there and how put 1,100 miles on it a week. Later we determined that the transmission wasn't completely installed properly so they put in a torque converter accessory that did something and I don't know what. So the dealer already admitted that the first tranny that went out was their fault and now the second one is giving me trouble. It was fixed for a little while after that torque converter piece was put in, but after about another month it wasn't shifting till about 4,500rpm and that was just cruising.... NOT pushing it. Well the original tranny was up against 400+ hp, but was a carb. Now it's back to fuel injection.

So now that you know the story heres the probelm. When I go down the road at a certian throttle positioning the thing goes up and down about 300 rpm like the torque converter is kicking on and off. It was last serviced in Bay City and they said they put Corvette parts in it. The main problem was fixed, but now this started and no one will fix it. The dealer it's at now said they don't wanna touch it even though it's UNDER WARRANTY. They told me to take it back to the last people that did the work and tell them it's acting up. Even the people that put in the new tranny originally said all I could do is not drive it in overdrive..... sorry but this is F***ing Bull****!:bs: What should I do here and does anyone know what could be wrong? Thanks

[fastblackmerc]

Alright first off it's a non Marauder question, but I still need help especially from those of you who work in the auto industry. Back in November I bought a new Ram Jet 350 Crate engine for my lovely K5 Blazer. About a month later the tranny went out so I bough a new one FROM GM with a 100,000 mile warranty. Now about a month later that tranny went out and did in the same way as the last one. I took it to a dealer in my college town (different from the one thatr installed it) and had it fixed, but they told me it was now out of warranty because it will never work for an engine this modified. I said what are you talking about the engine is stock.... all it has is an air filter... it's a crate engine from GM with a new tranny. The place that installed the engine also did the tranny so they knew what was in there and how put 1,100 miles on it a week. Later we determined that the transmission wasn't completely installed properly so they put in a torque converter accessory that did something and I don't know what. So the dealer already admitted that the first tranny that went out was their fault and now the second one is giving me trouble. It was fixed for a little while after that torque converter piece was put in, but after about another month it wasn't shifting till about 4,500rpm and that was just cruising.... NOT pushing it. Well the original tranny was up against 400+ hp, but was a carb. Now it's back to fuel injection.

So now that you know the story heres the probelm. When I go down the road at a certian throttle positioning the thing goes up and down about 300 rpm like the torque converter is kicking on and off. It was last serviced in Bay City and they said they put Corvette parts in it. The main problem was fixed, but now this started and no one will fix it. The dealer it's at now said they don't wanna touch it even though it's UNDER WARRANTY. They told me to take it back to the last people that did the work and tell them it's acting up. Even the people that put in the new tranny originally said all I could do is not drive it in overdrive..... sorry but this is F***ing Bull****!:bs: What should I do here and does anyone know what could be wrong? Thanks

Sounds like the tranny doesn't know if it should go into OD or not. If you increase your speed or shift out of OD does it stop?

[Motorhead350]

Yes it's only when my foot is on the gas in a certian position... like 1/4 throttle.

[mtnh]

I can't remember from my K5 days (1988-1992) whether the setup uses a kickdown cable from the throttle to shift to passing gear. This is a 700R4 transmission or newer? Anyhow, if this truck does have a cable that goes to the transmission, have it adjusted to factory specs.

One other thing: You haven't added any racing gas to this blazer, have you? :lol:

Good luck.

[grampaws]

Did they put in a modulation valve..
usually a vaccum valve at the back
of the trans..could be incorrect for
the application..
I am not familiar with this trans my not have
one..Query:confused:
What Corvette parts did they install??

[Motorhead350]

I'm not sure what Corvette parts they just said Corvette parts like a clutch or something. Also yes it did have racing gas at one point and what a difference it made..... not as much as the difference in the Marauder though. :lol:

[the_pack_rat]

:popcorn: :drink: :popcorn:

[1madmarauder]

im not sure if i can help but ill try. with the exception of my mm, im a chevy guy. what it sounds like to me is they put an electronically controlled lock up convertor in a cable controlled trans, or vice versa. does your truck have a detent or "kickdown" cable? also, whover told you about corvette parts is a moron, there is absolutly no and i mean no diffence just because its a corvette, the hard parts inside are the same in any 700r4, just as any other th350, 400 , 4l60, etc. only aftermarket mods would be different, like a transpak or something. if the trans is stock, vette parts are no better or worse. btw, what trans is in it?

[Motorhead350]

It's a 700R4. It's basically stock to my knowledge and has been to nothing, but Chevy dealers for service. Actually the place that caused this screw up just told me I can bring it back and they'll take care of it, but it's a hastle sense the truck is in Chicago right now and the dealer is in Bay City michigan..... yea this will be fun.

[David Morton]

If it's a 700R4 then it uses a throttle position cable.

The way to properly adjust it is to push the spring loaded tab on the throttle end of the cable housing and push the rack towards the cable, Then, push the throttle at the throttle body, not using the gas pedal all the way to WOT. The cable will automatically ratchet out the proper amount.

Now for the bad news. There's as many 700R4 transmission/calibrations as there are terrorists in Pakistan. They probably used one to match the engine but guess what? Unless there was one for a K5 Blazer that used that engine, you may have a transmission that can't account for the pressure requirements, 2-4 band servo size, fluid calibration orifices and accumulator valve spring sizes for each shift in a K5 Blazer. The 1-2 shift pressure and band servo on a Corvette may be fine for a K5 but try making the 3-4 shift with an extra 1/2 ton weight and the band may fry, caused by any of those systems.

If I was still doing that kind of thing, I'm sure I could fix it but I'd need to see it broke. Then I could tell what's lacking and beef it up. There aren't many guys that love the 700R4 that much any more these days though. I've heard a few companies are making 700R4 racing trannies, beefed up and all pretty much bullet proof, to a point. It's a beautiful design, simple (the only one I know of that gives reverse and 4 forward gears using only two planetary gearsets, ours uses three) and very compact and light. BTW, the same clutch and gear stack is used in the electronic shift version, the 4L60E.

Call a GM service manager and ask him if he knows of some oldtimer that used to work on this specific type of tranny back in the 80's. You may be better off with a guy like that working on it.