I suggest power washing the underside of your tranny and whatever else if full of oil and dirt. That way you can see where the problem is.Its most likely a seal.
Yes there were AOD trannies in 88. Weather or not yours is I cannot tell.lol

 

If you have an overdrive indicator, looks like "(D)" - a D with a circle around it, then you should have overdrive. Unless somebody swapped the trans out and didn't change the indicator or installed an auxiliary overdrive unit. In those two cases you'd have to look underneath to know for sure. This thread might help you identify your trans.

http://fullsizebronco.com/forum/showthread.php?t=49569

 

I agree with Pantsman, the AOD should have a PRN(D)D1 indicator. If you put it in D, it should shift 1-2-3 only. In (D) it should shift 1-2-3-4od. Moving it from (D) to D at highway speeds you should feel it downshift if it's in overdrive. Check out that link he gave you, it's a good one.

Also, just to be sure, you are checking the trans dipstick with the engine running, right? The engine should be warm & the trans in Park to get a correct measurement.

 

With 33s and stock 3.55:1 gearing, you should be reading about 1650RPM @ 60 in OD. Your quickest bet is to look at pictures of the C6 and AOD pans, and determine which one you have.

Which is yours? (http://www.ford-trucks.com/forums/420083-trans-pan-id-guide-e40d-aod-c4-c6.html)

They did not put the OD selector on the stalk until 1990 or 1991, I think. So yours should either be on the dash, or mechanically selected from the shift selector.

Also check out the link below. It lists gear ratios for the AOD and the E4OD:

http://www.fordification.com/tech/transID-auto.htm

You have a 2.40:1 1st gear, so while your fuel economy would suffer slightly, adding a 3.73:1 gear would put the operation of your tranny at or near the numerically higher E4OD's 1st gear ratio of 2.71:1, and would help you recover the lost gearing from going to the 33s.

 

In regards to El Kabongs question, I had the engine nice and warmed up for at least 10 minutes of running and in park when i took the reading and it didnt read anything on the stick. After I added the quart and a half it came up. Still very rough when shifting from P to R but ive read that, this issue is common. As to razorfly, at 60mph its at 2500rpms and stays there untill i go lower than 50 and it gets down to 2000rpms. Plan on power washing it as soon as i can jack it up enough to really get a clear shot. I will look at my pan and see which one i have later today. I dont have a (D) or D1 just PRND12. Will test on the way home from work how many times it shifts up and down. Best part of it is trying to figure out which is drive, netural, and resevse seeings as how after replacing the Turn Signal Switch the Transmission indication cable dosent want to work.

 

Best part of it is trying to figure out which is drive, netural, and resevse seeings as how after replacing the Turn Signal Switch the Transmission indication cable dosent want to work.

There is typically a "little string on a spring" with a loop that you have to hang on the shift indicator. I don't know if yours has one, but if so, it would be an easy fix.

 

Count the clicks on the shifter, From park, 1 click is reverse, 2 clicks is nuetral, 3 clicks is overdrive, 4 clicks is drive. You may just be missing and putting it into drive instead of overdrive, aftter you power wash it make sure it goes into park FULLY. My old 89 had this issue it sucks but when is overdrive it would be in drive so I bumped the shifter and bam had overdrive again. Something like a quick tap, also when checking on the highway LEAVE YOUR CRUISE OFF, just asked what happened to my bronco when I forget to take the cruise off.

 

My 86 has an AOD = automatic over drive, PRN(D) DL where the 1st D is 4 speed OD and 2nd D is a 3 speed, the way to tell what transmission you have is to count the "pan bolt pattern" ie: AOD has 14 bolts, E4OD has 17 bolts and I'm not sure about the C series...go here: www.broncolinks.com ~ under the transmission section and scroll.

The AOD's have a TV throttle cable and "adjustment" on top of the TB at the linkage and there's also video on FSB, possibliy a You Tube...? ..showing you exactly how to, takes less then a minute to perform...so "search" or check the Haynes Manual ....it's important to have this adjustment correct or can seriously affect the transmission itself.

There is also a procedure to "syncronize" the column shift linkage and transmission so that each gear is in it's relative position shifting thru PRNDDL etc. It's listed in the Haynes Manual, transmission section, Illustration: "Point A" with directions, also listed on broncolinks. Procedure takes 10 -15 minutes max.

Other transmissions may be different in that they may have an similar adjustment or "electric solenoid" on the side down below that may be corrected or needs to be replaced...

While you're at it why not service your transmission with a filter kit and fluid....my AOD only cost $30.00 for filter kit and fluid..takees about 1 -1/2 hr start to finish. Other common sources for leaks can be the pan gasket or dipstick tube, the AOD has 2- O rings on the dipstick tube end where it goes into the case.....OR the seal is leaking inside behind the "torque convertor"...PITA where you have to drop the tranny and pull out the TQ in order to replace it..

Good Luck ~

 

Got home and my obd1 reader was in so i did a KOEO test and it came back with the codes 67, 33, and 63. 63 reads that it is Throttle Position Sensor Circuit Below Minimum Voltage, 33 reads that it is the egr valve not closing properly, and 67 reads that it is neutral/drive switch circuit open. Im wondering if the EGR Valve might also have something to do with me only getting 11mpg highway going no faster than 60mph. Maybe i should go ahead and replace the O2 sensor while im down there sense it looks really worn on the wires and around the unit itself that joins to pipe. Also the exhaust smells rich almost choking if not use to the smell (I know Carbon Monoxide.) I have no idea if the cats have ever been replaced. I think the PO put a cat back exhaust that is rusting out as it is now already done one patch job right behind where the cat joins to the exhaust. Trying to gather enough money to put a nice exhaust system on it. Continuing to search the sight for more solutions on these codes.

 

What OBDI code reader did you purchase? I'm in the market for one, myself.

 

sounds like the nature of the beast to me I get 12mpg's with an E4OD overdrive 32" tires and 3.55:1 gears with a 302 H.O. roller that has a sixlitre tune up and K&N filter TB spacer(it was in the truck when I bought it)

 

Ramsey,
What kind of mileage are you getting on the open road?

 

The OBD1 reader i bought was $20 from handsontools.com and its an innova obd1 reader. I get 11mpg on the highway and light city traffic. I dont go over 60mph either. So i know its got problems.

 

Regarding code: 67 ~ AC or NSS...read my 3rd paragraph, post #9....in many cases adjusting the shift linkage with the trasmission to syncronize them (PRNDL) will solve the code 67 issue....I found this out when I turned the key to RUN my reverse lights would come on while Park and sometimes when I would go to start the Bronco I had to lift the column shifter up so it would start, the adjustment corrected both these issues...

So before you go crazy playing with or replacing the NSS find the correct adjustment procedure for your BKO....see what happens..


Good Luck ~ :thumbup