Old Guy...one question. My C4 was built about 4yrs ago, and the builder used Dextron in it, when it was built. Will it hurt the trans? Seems to be ok, no slips that I can feel. If I change the fluid to Type F, will it be ok, or hurt the trans? Also, will a good trans shop be willing to do that, and get all the old fluid out. Do they have the means to clean it out well, and replace the fluid? More than one question, I know, but you seem to know these transmissions better than most. Thanks, Earl
I was going to ask this same question, because my 71 Grabber does the same thing. Plus my friends 78 Chevy Truck has been doing it recently. Thanks for all the info.!!
You can get most of it out yourself, at your home. Only problem would be draining the converter. Unless it has a drain plug, you won't be able to get it all out without putting some more fluid in it and mixing the fluids, then draining the pan again. If it has a drain plug in the converter, you could drain that, drain the pan, etc I use type F in everything... GM, Chevy, etc I once put a quart of Dextron in my Ford because the middle of nowhere gas station only had that there, and i was 2 quarts low and it would try to kick in/out of gear going down the highway (converter "engaging" then not) I had no problem with it, and seemed to work fine. I wouldn't recommend this all the time but it works. Anyways, if you want to put type F in it, go ahead, just drain everything as much as you can, and fill it back up with Type F... should be no problem at all. I've done it
There are two sides to this deal, first is the mixing of fluids. I try to not do that if possible, but really think it would not hurt anything. However, have seen instances where taking out old fluid would actually cause problems because the grit and goo in it was actually making the trans work decent. If you have taken care of yours as I suspect, should not hurt a thing. The other deal is F is what was recommended by Ford for these tranny's and probably should go by that. Andy has good point on the converter, some shop's have a machine that drains and flush's the whole thing. Usually charge close to 100.00, but most shops just drain the pan and put in new fluid. F will shift a tad harder in newer trans, and especially in the GM glide's for racing. Drain plugs are not installed at the factory, in the converter or pan so that the customer will have to take it to the dealer for regular service etc. JMO , it is a bit messy to do without them, get a big under the bed plastic storage box and loosen the pan so that you can pry one end down. After most fluid is out take it clear off and change the filter and clean the pan, if you can, let the fluid drain overnight and a lot more of it will come out, but not necessary if time won't allow. Drain plugs run about 5.00 and are easy to install with a drill and hand wrenches. Must put it in a spot in the pan that it won't hit the valve body parts etc. Cost of you doing it will run about half of most shops charge. Go for it. TE=Earl Branham]Old Guy...one question. My C4 was built about 4yrs ago, and the builder used Dextron in it, when it was built. Will it hurt the trans? Seems to be ok, no slips that I can feel. If I change the fluid to Type F, will it be ok, or hurt the trans? Also, will a good trans shop be willing to do that, and get all the old fluid out. Do they have the means to clean it out well, and replace the fluid? More than one question, I know, but you seem to know these transmissions better than most. Thanks, Earl[/QUOTE]
Thanks Dave. I am going to take a look and see if I have a drain plug on the converter. If not, I may take it to a shop, and have a plug installed while I am there. A bit more money, but, might just get it done all at one time, and done correctly. I will let you know how it turns out.
You'll spend quite a bit more money at a shop easy way to check for drain plus is turn ot over by hand w/ a long ratched and a socket, or have someone bump it over from above... (not the safest thing in the world but I've done it many many times) If you put in a new converter with the tranny, it might have a drain plug In my book, Id change the fluid yourself. Even if you have to buy the "under the bed storage box" that is famous around my house and Daves... your out maybe 30 bucks. Buy the fluid you'll need, new filter/gasket, drain plug and your out maybe 30 bucks... 40 tops. Well worth it, a shop will proboally charge you over 100
To clarify my earlier post about checking for the drain plug. I was referring to the plug on the converter. Also, while your changing all this stuff out, it's a good time to install a tranny fluid cooler (if not so equiped at the current time).... When I redid my transmission on both my trucks, I put in a big aftermarket oil cooler, electric fan, and deeper transmission pans... Ran less than 150 bucks total.
I think it was on some trickshift advertisement but I once read that type F was just one step below what trickshift is and it was the best overall stuff to use. It stood up to heat and breakdown really well. Like what was stated above Dextron was intended for the materials used in those specifed trannys. I use a mix of F and trickshift and mine is doing great. I love those second and sometimes third gear scatches.
I wont buy the trickshift, looks just like type F to me... and I can get a 3rd with a stock 302/c6 in a 76 F-100, its kinda hard to do, but w/ the shift kit I have, it'll bark it a bit Second everytime
