Overdrive auto transmission / ABS optional?

[dshockley]

Two questions:



Was ABS optional in early 1991? Rear only? I have not had a chance to crawl around on my truck much and would prefer that it not have it. It hate ABS on a heavy truck!



When did an overdrive automatic transmission become available? Was it an option? and What transmission is in my truck? Are there any upgrades available for it?



Thanks for all the help in advance.

Dan

 

[Midnite]

Not sure about your other questions, but if you have a square button on the dash between the steering column and the heater controls labelled "O/D Lockout" then you have an A518. It's basically the old 727 three-speed auto with an overdrive unit bolted on the end.



Mike

 

[dshockley]

OK, No button. Does that mean that I have a 727? When did the OD become available?



Thanks

Dan

 

[JFitzgerald]

I can't help much with the auto, but the ABS system is rear only, and has caused some folks some problems. The ABS controller on mine is unplugged after trying to get the warning light to go out. You can get to it by pulling the glove box open beyond its' stop. I believe it says Kelsey-Hayes on it. No apparent side effects from unplugging it. Brakes work fine even pulling the big trailer.

 

[Wayno]

The OD came out in the 91-1/2 year model trucks,along with the inter cooler and the cross flow radiator. And yes you have a 727 transmission, at least that is what I have always been told.

 

[Midnite]

Originally posted by Wayno

The OD came out in the 91-1/2 year model trucks,along with the inter cooler and the cross flow radiator.

I don't think that's right--my friend's truck is (I believe) a '90, and he does have a 4 speed auto. While I'm not too clear on what year his truck is, it does have the older '89-'90 style grill, and does not have an intercooler.



Mike

 

[Thierry]

Someone may have changed the transmission out on his truck to a o/d

trans.

89-91. 5 non intercooled, non crossflow radiator auto trucks came with 3 speed 727 trans with 3. 08 rear gears



91. 5-93 intercooled, crossflow radiator trucks came with o/d 4 speed trans

with 3. 54 or 4. 10 rear gear sets