Before I add the wrong fluid, I just want to make sure of what to put in there.
On an 88 Bronco with a manual 4spd w/overdrive, do I use standard tranny lube or is there another type? Not sure which model trans I have either. The ID tag says
E8TA
JE
194009
Can anybody help?

 

Sounds like the M5OD transmission. The manual calls out for automatic transmission fluid, I used mercon or Dexron III. Watch out for leaking on this transmission from the rubber plugs on the top plate. Search the forum for this and you will find info, the leaking plugs is a known problem area for this transmission. When you state 4spd w/overdrive I am assuming that it is the 5 speed.

 

Thanks. I did find out that it is the mazda (5spd). Threw some mercon in there with some Lucas. I'm afraid that the damage is done already. The leak was coming from the top of the trans, most definitely the rubber plugs. Trans is noisy and I get some serious vibration at around 30-40 mph. Should have checked it sooner.

 

If the transmission still shifts good, it is possible you are dealing with drivline vibration issues such as bad U-Joints. I would not be ready to call the transmission dead at this point without further investigation. One of the first signs of low fluid is poor shifting where the shift lever takes a lot of force to move it through the gears.

 

Truck still shifts into gear without effort. I had it on the lift and my buddy (a mechanic) checked out the u joints and said they were fine. I am under the impression that the vibration is coming from the tranny because I think I feel it in the stick. Also, when the truck is coasting in gear like on a downgrade, I hear this noise (like gears not meshing right) that sounds like an engine brake from far away...if that makes sense. Either way, I don't intend to put any more money in this thing so I guess I'll drive it until the tranny drops or just sell it.

 

I'll buy it! Is it a 5.0L? My trans isn't vibrating, but I'm having trouble getting into 2nd and 3rd, esp. downshifting. Lemme know what you found.

 

mtm1972,i'm having the exact same problem with mine.I was also thinking about adding lucas oil to it to see if it would quieten it down,but it sounds as if it didnt help yours.I may try it anyways,mine isnt really that bad yet,but I got it for a work truck and dont want to spend a lot on it.I f the lucas dont help,i'll just have to deal with it.

 

I build 2-3 to of these trannys per month. They are very simple to work on and take no special tools. Yes the plugs are a problem, but a simple one to fix. Some new plugs with a little RTV. If you have one of these type trannys and it is not leaking, a good weekend project would be to drop it out and reseal it. it will cost less than 30 bucks and save you a bunch more.
Oil starvation is the main killer of on these units, with the front bearing and input shaft usually being wiped out. The trick is to fix it before the lower fixed gear set is thrashed. then unless you can find used parts it gets exspensive.
A small parts kit with new sync rings will run 100- 135 bucks. If your mechanical abillity runs farther than where do I put the gas and oil, you can rebuild this tranny. For far less than 500-700 the salvage yards are asking for a used unit. Before you start go to your local Ford dealer parts man and have him give you an exploded view parts sheet. This help in disassembly and reassembly plus help ID parts you may need.

Pat

 

It looks like I was only down a quart or so. I added a lucas/dextron mix. It didn't do anything for the vibration/noise initially but after about two weeks, I don't have the same symptoms I was having. I mean, I was having heavy vibrations and the steering wheel was shuddering at certain speeds/rpm's. Maybe it wasn't my tranny after all because I doubt tranny probs work themselves out. Either way, the truck runs smooth again for some reason so I'll keep driving it around...