Looking to buy a rear end out of a 84 Z28 L69 Camaro, when I looked at the RPO codes, it had a code of "GT4". I know that is a 3:73. The best gearing ive seen has been 3:42's in the 5 speeds. Was the 3:73 a factory gear in the third gen camaros? Or special order?
Had to take a pic of the codes just so i could ask u guys lol

Had to take a pic of the codes just so i could ask u guys lol
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Couldn't say about "the first you've ever seen"; but being as how it's a L69 car, yeah. Maybe you just haven't seen many L69 cars?
That's what my car had. (has)
That's what my car had. (has)
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That's what my car had. (has)
Wasnt aware that any had this gearing, L69's or even the 1LE'sOriginally Posted by sofakingdom
Couldn't say about "the first you've ever seen"; but being as how it's a L69 car, yeah. Maybe you just haven't seen many L69 cars?That's what my car had. (has)
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Yep, L69's (though IIRC, the automatic version in 84 was equipped with 3.42's)Originally Posted by bigarmzz
Wasnt aware that any had this gearing, L69's or even the 1LE's JamesC
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[QUOTE=bigarmzz;6057958]Looking to buy a rear end out of a 84 Z28 L69 Camaro, when I looked at the RPO codes, it had a code of "GT4" and "D80". I know that is a 3:73 posi. The best gearing ive seen has been 3:42's in the 5 speeds. Was the 3:73 a factory gear in the third gen camaros? Or special order?
It's A 3.73 But It's Not Posi,D80 Is A Spoiler,G80 Is Posi.
It's A 3.73 But It's Not Posi,D80 Is A Spoiler,G80 Is Posi.
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deleted. need to re-learn my '84 facts before commenting.
[QUOTE=gt4373;6058038]
Quote:
It's A 3.73 But It's Not Posi,D80 Is A Spoiler,G80 Is Posi.
"G80" not "D80", cant believe I got those wrong lol, blonde momentOriginally Posted by bigarmzz
Looking to buy a rear end out of a 84 Z28 L69 Camaro, when I looked at the RPO codes, it had a code of "GT4" and "D80". I know that is a 3:73 posi. The best gearing ive seen has been 3:42's in the 5 speeds. Was the 3:73 a factory gear in the third gen camaros? Or special order?It's A 3.73 But It's Not Posi,D80 Is A Spoiler,G80 Is Posi.

sofakingdom
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Yup, the L69 5-spd cars AFAIK ALL had that gear. But most, maybe not all, of the 84 auto ones were nutted with the 3.42s.
1LE cars didn't come with the good gears. 3.42 at best in the 5-spd ones.
1LE cars didn't come with the good gears. 3.42 at best in the 5-spd ones.
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The RPO label is MX0 automatic, L69, and GT4. GT4 3:73 was optional on the LG4, but not with L69 automatic per brief look at GM Tech Data. May be missing it. My 'memory' says 3:73 was optional on L69 auto.
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Quote:
3:73 was optional on L69 auto
That's what I seem to recall as well, but only for 84. Which, for that matter, was the only year the L69/auto combo was available in these cars at all, anyway. 3.42 standard, 3.73 optional; 3.73 standard for the stick ones. AFAIK 3.73 was standard in T-5 cars in all years with that engine.3:73 was optional on L69 auto
My late little bro had a 87 MC SS L69/auto/3.73.
G80 (posi) was very uncommon in the early years of these cars... I've heard any number of excuses for why, but I don't know which if any are true.
xxxxxx
Thirdgen89GTA
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1LE cars didn't come with the good gears. 3.42 at best in the 5-spd ones.
In truth though, for the road racing purposes intended the 3.42's were plenty. 3.73's would have been overkill considering TPI's powerband. In a road racing environment you spend very little time in 1st. Sometimes tracks you don't even touch 2nd. So the 3.42's were a good middle of the road gear in a series that didnt' allow you to change the car to suit the track.Originally Posted by sofakingdom
Yup, the L69 5-spd cars AFAIK ALL had that gear. But most, maybe not all, of the 84 auto ones were nutted with the 3.42s.1LE cars didn't come with the good gears. 3.42 at best in the 5-spd ones.
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Night rider327
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Yep one of my parts cars from last year was an '84 trans am, L69, auto. Had a factory 3.73, disk brake open (non posi) rear under it







