Hi Guy’s Ok a quick update on my car and a question as well. The car has been out this month from its long winter rest and it’s performing great. I’m pleased to say that I managed in the end to get some new outer door mirrors to replace the ugly European one’s that were fitted (See below) The mirrors were courtesy of Classic Industries in California who provided an excellent service delivering them in only four days! A few coats of paint and some lacquer later and the mirrors look as sexy as the car. Ok here comes the question. While changing the engine oil I had a good look at how I would undertake the removal of the oil pan to change the transmission oil later this summer. I noticed that although most of the bolts on the pan are easy to get to, the bolts at the rear are completely covered by the transmission cross member. I’ve tried all my tools to try to get to them but to no avail. In the Haynes manual it doesn’t say anything about having to remove the cross member to get to them, but I think this is the only way. Would it be ok to use a jack to support the transmission while I remove the cross member and is this the way it should be done? Also while I was down there I noticed a number stamped on the transmission above the selector cable which read 8663550 does anyone know what this is? Any help would be appreciated. All the best. . . . . . . Speed.

I used a tranny to support teh tail shaft part of the tranny when I changed the filter on my tranny. No big deal, just has the potenial to be messy

Maybe serial/ p/n for the tranny?

I do not know but I hear that after 75,000 original miles have gone by without a tanny fluid change. It will most likley cause more problems if you change it now.

From my understanding, when tranny fluid is not changed regularly it will start to break down and be come detergent like. When draining it, that will strip the tranny of all lube and just replacing the fluid wont correct the prob. Is that accurate?

I think you geting at is: The fluid is going to have bits & peices of teh clutch pak material floatring around in it to help keep the friction up. When you drain the fluid, those peices go along w/it, and when new fluid is added, your not going to have those pieces to help keep teh tranny shifting right, so it appearsto "suddenly" sart slipping.

yea something like that.
but the 700r4 is just more touchy about it.

But what isn't the 700r4 more touchy about [then others] until its built well and maintained well or out of a vette.

The 700 is like any other transmission dude. It's not "more touchy"......

Just 2 months ago I had to pull the Mazda tranny in my moms Ford and have it rebuilt becuase she went 65,000 miles without a fluid change. $1000 dollars worth of neglegence.

I heard you should change it every 2 years or 25,000 miles. Mine is almost due for a change. Are any of the tranny filters better then others? Or are they all basicly the same?

The 2 back bolts were not hard to get to on my car. I fi remeber correctly i just used a small socket wrench to get to them.

Erm, great cheers fellas.....so now I still don't know if it's ok to support and unbolt the cross member, but I do know that if I do manage to change the oil it'll probably ruin the box!

I'll give it a go later i the summer and let you know if I've still got a box worth shifting with!

P.S. The oil in my car was only changed 2 years ago and has only done 1,500 miles since (still a nice red colour)


Speed.

I wouldnt worry about it if it only has 1500 miles then.

support the tail end w/a jack & remove the crossmember.

I still dont see why you would need to remove the cross member. I did mine with the cross memeber on and i have the exact same year car as you.

Believe me no way, the cross member goes right over the rear bolts. You have about 1cm clearance between the cross member and the back of the pan and the bolts are under it. I wouldn't be suprised if it was because the car was shipped to Germany first off and they mounted the box more rearward for some reason. I don't know I'll try the jack thing anyway.

The owners manual I have says that the fluid should be changed every 2 years regardless of mileage. Besides I want to get to know the car and service it best I can so it'll give me something to do next holiday

They must have used a different crossmember. I can slide a socket along the crossmember so it fits between the crossmember lip and the trans pan. Then I get the socket onto the bolt head, and finally, I clip a 7" extension & ratchet onto the socket.

The 700r4 went through a bunch of improvements to it's design. First design was 83-84, and they were poor. Some improvments were made in 85-86. The MOST improvements were done in 1987, and the trans was further improved somewhere around 89-90. As GM had more experience with the trans, they were able to improve it's reliability and longevity.

I think you'd be fine with a trans fluid change, simply b/c your trans is a 91, with the most improvements. Check the fluid now. Is it still red? Does it feel slimy still, or is it gritty? If your fluid is dark red/black and feels like sandpaper and smells "burnt", you trans is about to die, don't change the fluid. But if you're still red and it feels "slimy" and smells "oily", your trans should be okay. You said it's still red, so check the "feel" and "smell".

Fact: Heat kills trans fluid. It causes the fluid to break down and lose it's lubricating properties.

Fact: By design, the 700r4 runs hotter than other transmissions!! Adding a trans cooler (I put the B&M one on) will keep your trans happy and your fluid will last longer.

Because of those two facts, the 700r4 fluid should be changed every year. I guess an exception would be if your car isn't a daily driver. If you're throwing the mileage on and driving it every day in normal stop/go traffic, you'd better be changing that fluid once/year.

Tip #1: When you drop the pan, and remove the filter, make sure the o-ring that stays on the filter's neck comes down. Sometimes it gets stuck up in the trans hole. You must remove this old o-ring and use a NEW o-ring!!!!! The new one will be on the new filter. Don't re-use the old!! This ring has a metal band inside so it will be a pain to remove if it gets stuck inside the valve body... you might want to use a small screwdriver to try and pry it down.

Tip #2: When the old filter is in your hand, take a set of angle cutters to it, and cut the filter open. Unfold the paper filter medium. If there are large chunks of metal in there... well, start saving for a rebuild.

Tip #3: NEVER put sealant on the trans gasket! The pan flange and the trans flange must be 100% dry to prevent leaks. I wipe the flanges like hell with a paper towel over and over and over and over again until they're bone dry, and then quickly put the pan up and snug up all the bolts. One drop of trans fluid on that gasket and you'll get a leak. Install it dry, and you'll be leak free.

Tip #4: The bolts are STEEL going into an ALUMINUM case with ALUMINUM threads!!! Whenever this happens, that means the max torque spec is 15 ft/lbs!! Don't super-tighten those bolts!!! And tighten them in a criss-cross pattern, in stages up to final torque (because you all have torque wrenches by now, right!), to make sure the gasket seats properly.

I use the Purolator trans filter set, part number P1195. For the gasket, I use Fel-Pro # TOS-18663. The Purolator set does come with a gasket, but I keep them in a box as "emergency" gaskets. The FelPro gasket is thicker, and all the bolt holes are slightly smaller which allows the gasket to "hold" the bolts as you put the pan up. On the Purolator gasket, only 4 bolt holes are smaller.

Is purolator filter better then the one you get at autozone. Or would i be better off getting an ac delco filter. Im putting a big order in with gm partsdirect so i think i might add that on too if it is better then the 2.

Depends on what year you were born.

for high miles with little service and lots of abuse the 700r4 is a dog compared to a turbo 350/400 or even the 200r4. Guys run monster big block Buicks through the 200 with great results.

ANd mazda don't really count. no forign car does. espically a fod using forign parts.

But the 700 can be a rock if treated right. abuse it and good luck.

how many people know a guy with an old chevy truck with 10 million miles on it and the only thing he ever does is add fluids. never changes them. you could never do that with a 700.

My tranny & crossmember are the same way.

If my car wasn't so frickin' low, I could slide under and check. Next time I get the car up in the air, I'll break out the ruler.

Thanks for the feed back guys,

I’m in the process of changing the auto box fluid in the firebird and as usual nothing in the Haynes manual resembles what I have in my car. In the book it says the auto box oil filter is held in with two bolts, and resembles a flat plate with a filter on it.
But in my box the filter came away with the oil when I lowered the pan, and hence I didn’t see where it exactly came from! I’m assuming that the small hole at the front of the box is where it dropped from and no the small ‘O’ ring didn’t come out so I guess I’ve got to go and look for that.
Thanks Tom for all the technical info on the box, I guess this is why my box is nothing like the one in the Haynes manual. The oil in the box is still red and viscose there was however an accumulation of what appeared to be very fine slimy silver Grey mud built up on the magnet in the pan. I know your all going to tell me that this is the vast majority of my gearbox and I’ve got serious trouble looming. I’ve not cut the filter up to look inside but through the large hole at the end of it I think there’s whats left of a degraded filter, If you stick your finger in it feels just like a piece of course grade sand paper! No large metallic bit’s as far as I can see but I fear the worse already.
The box works beautifully at the moment but I’m now worried that I might have made more trouble than good by draining the oil! I’m still waiting for the genuine AC Delco filters and gaskets please don’t tell me that sitting without oil in the pan will make matters worse!


Speed.