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4l60 trans upgrades.

J

jesse james 1

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Hello everyone, I have a 1991 blazer/350/4l60. About 10 years ago I had a Road Ripper 1000 trans put in my rig. Since then I've put about 40k miles on it. Every now and then it would puke a little fluid out of the trans vent when just cruising down the road. Was never impressed with the way it shifted either.

Yesterday I was leaving town and cruising up to speed and suddenly blew a lot of fluid out and lost 3rd/4th gear. Dumped half a bottle of fluid in and idled home in 2nd. When the trans shop gets it apart what upgrades should a guy do? Just go with what the shop recommends or any specific parts to use. It's a cruiser on the weekends and gets used for farm work almost daily now that I've done a pile of work to it. Thanks for any input.
 
Babaganoosh said:
Toss everything Sonnax has to offer.
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It's a good concept, but there's still a lot of decision-making needed. Sonnax must have 100 parts for this trans and many of them are mutually exclusive. I also assume you're not recommending the 2.84:1 ratio planetary, for example. Some of the upgrade parts make more sense when you're starting with an earlier model, whereas they aren't as much of an upgrade on the later ones. Some of the valve repair kits really aren't needed unless you know the bore is worn out. A lot of the valvetrain parts require special tools for the machining. Buying all of those for 1-time use might push the numbers in favor of having a shop do it that already has those tools (or will amortize).

That's why I said it's good to know what you're starting with, what the real failure mode was and the condition of many of these parts, rather than just tack on another couple thousand $ for the concept.
 
centexk5 said:
A 4l80e is a great upgrade for a 4l60e.
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His is a 4l60, meaning 700r4

Now I happen to have an 84 turbo diesel with a 700r4 that is telling me it is not too happy, and I happen to have a 4l80E and the stand alone controller from a 92 turbo diesel so I am contemplating that switch now.
 
Blue85 said:
It's a good concept, but there's still a lot of decision-making needed. Sonnax must have 100 parts for this trans and many of them are mutually exclusive. I also assume you're not recommending the 2.84:1 ratio planetary, for example. Some of the upgrade parts make more sense when you're starting with an earlier model, whereas they aren't as much of an upgrade on the later ones. Some of the valve repair kits really aren't needed unless you know the bore is worn out. A lot of the valvetrain parts require special tools for the machining. Buying all of those for 1-time use might push the numbers in favor of having a shop do it that already has those tools (or will amortize).

That's why I said it's good to know what you're starting with, what the real failure mode was and the condition of many of these parts, rather than just tack on another couple thousand $ for the concept.
Click to expand...
I didn't mean literally everything, obviously some of it isn't needed but the upgraded valve body and other stuff is nice to have.
 
The shop got the trans apart, I was driving when they called so didn't get a chance to write everything down, but sounds like the 3-4 accumulator cracked and broke burning up the clutch packs. From what I remember it sounds like for sure, clutch packs, sprag assembly, valve body upgrades that dont rely on the TV cable for shift points, (must be computer controlled? Idk) torque converter, upgraded accumulators. And I'm assuming bushings, bearings, seals ect... I'll get more specific details this coming week.
 
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