What letter do YOU use?

[JamminG4Jim]

Hi everyone.

When I first bought my explorer I read the owner's manual like it was a best-seller!!! There WAS one part of it that didn't quite make sense, tho. So, here goes:

When I'm driving around and NOT on the freeway, should I use D or Over-D????

I'm getting conflicting reports from people. Some mechanic's I know say "Only Use O/D on the freeway". Others have said (and the Owner's manual seems to hint) that regular D should be used to get going while towing.

My dad blew up a tranny by running it in the wrong letter (70MPH in D, sheesh!!!!) .... I'm just looking to put the least amount of strain on my tranny...

So, whad'dya think?

 

[Brian1]

OD unless it is really weighed down or pulling a trailer then you would use D around town. Just my opinion from what I have heard.

 

[2001ExpSport]

You can use OD all the time. OD is just the 5th gear and it will engage the 5th gear(OD) at about 45mph. It is a mpg thing. Also, taking it out of OD will chaneg the way it shifts. With OD on, the tranny will not downshift for breaking. With OD off, the tranny will use the gears for breaking like downshifting with a manual.

For towing I would run in OD OFF mode. For around the town you can us OD ON. Try yours both ways, you will be able to feel the tranny down shift early to help in breaking.

 

[Exploder99]

i frequently hit the O/D button as an engine brake. it helps to stop the car in shorter distances. i guess i miss stick too much.

 

[zensius]

There's been a lot of talk on this site about O/D killing these transmissions. Apparently from what I've read, the automatic is not very strong. Many Tranny shops have reported the fatal flaw is the overdrive. So they recommend using it only on the highway.
Yes, O/D should be fine for around town but if you want your tranny to last, and I do (I'm on number 3), you'll get in the habit of driving around town in D. And using O/D above 45mph.
It can't hurt. Just my opinion.

 

[JamminG4Jim]

I want to thank you all for posting your replies!!

I hope others will also!!

It seems to me that my tranny is constantly shifting when i'm cruising in town. That in itself can't be good for it. I live close to St. Paul,MN. The city our illustrious Govenor says has street names thought up by "Drunken Irishmen"... The speed limits haven't changed since the horse N' Buggy days, and we also host one of the only stretches of Interstate I-35 that has a 45MPH speed limit!!!!!

So, It's D for me, and O/D over 45 !!!!

 

[sink]

I think your conclusion is good. I find it hard to believe a tranny would blow from running 70 in D. Maybe the vehicle had super low axle gearing. In the old days, and on my 1980 PU, cars only had 3 auto gears and they ran them past 70. -I was with a friend in a rental topaz once and he was goofin and ran it up to 60 in Low 1. I kept yelling "its gonna blow- shift it, shift it.." LOL. I figure he took a couple years off the engine, it was hanging 6 grand RPM!!!

 

[2001ExpSport]

To be honest, I would rather run OD off in town. My '01 likes to hunt around for 5th(OD) at about 40 and it gets annoying because I can feel it shift up then down like it isn't sure which is the best gear. Unfortunately, the OD is reset when you shut off the truck so it has to be turned off(in my case) every time I start up. The '01 trannys are ALREADY having recalls so I may just get in the habit of switching OD off from now on except for the highway.

 

[sink]

It seems we have a little apples-and-oranges action here. I think it is OK, but want to point it out. The original question was on a 94 like mine, it seems you newer folks have electric PB OD. Does anyone know if the 94 vintage transmissions and the newer ones are different in actual hardware for the OD gear train and clutches? I don't know, but this made me curious.

 

[Peter Weber]

As far as I understand, the newer AT with the pushbotton OD have an extra gear added between 2nd and 3rd making it a 5-speed.

I never owned an Explorer with the previous AT, but wasn't it a 4-speed with 4th being OD?

 

[FlyAU]

Originally posted by Peter Weber
I never owned an Explorer with the previous AT, but wasn't it a 4-speed with 4th being OD?

Yes.

I leave it in O/D when I drive...from what I've been taught, put it in D when towing and 2/1 going down steep grades to use as engine braking. But, my best friend just bought an Expedition, so I don't have to tow his jet skis anymore (kinda hard for a Maxima to do that). And there aren't any steep grades here (frickin' flat as a pancake!).

 

[Alec]

I think my tranny is is a four speed: 1, 2, D, OD. It's a 96, so has the pushbutton instead of two spots on the shift scale. I turn OD off when towing below 70 mph (almost never go above that anyway while towing), for passing on the highway, and sometimes to assist in braking. OD will automatically turn back on in mine at 80-90 mph, depending on RPMs; usually 87.

For me its very important not to run boost in OD, that's supposed to kill the tranny 'cause OD is supposed to be a cruising gear, and can't handle all the power. Besides, turning it off manually saves me a downshift when passing or accelerating.

 

[Alec]

BTW, I just remembered my dyno runs were done in 2nd. The speedo got a little above 100 before the rev limiter kicked in (~5300). Also, my truck frequently gets above 60 mph in first gear when accelerating hard.

 

[srpauliesr]

OD. I use "D" for slowing down when getting off the highway to save a little on the brakes.