Opinions on auto tranny issue

Big Bore · Jan 31, 2015

Well I think my tranny is toast, although I've yet to dig into it since it was towed home last night. For the last few months I've been having an issue with it not engaging in reverse, requiring raising rpms then it would grab. Couple weeks ago it started doing the same in drive from a stop, rev the engine and it would engage. Once moving there were no problems. Yesterday while battling some snow getting firewood it made a slight grinding noise at one point which I thought might have been the t-case popping out of low range, which has happened a few times in the past, but turned out not to be the case and after that I could not get it to engage. I feel it might be the TC, however I have not ruled anything out including the possibility of it being the t-case. I prob won't get to assessing it until tomorrow mostly due to the fact it's 27 deg outside right now. Any and all opinions, ideas, or magic trannie spells are welcome and appreciated.

lincolnlocker · Jan 31, 2015

mark Kovolsky would know whats up..

live life full throttle

Big Bore · Feb 1, 2015

I'm starting to think possibly it might just be the TC, although that was a custom built triple disk billet job. The reason I'm thinking it might be the TC is a couple years ago my trans cooler lines rubbed against each other and were leaking really bad for about 120 miles before i became aware of it, I was towing a trailer over several steep grades and passes. I remember the trans making the same grinding sound when I pulled off to the side of the road to let people pass and was in a bit of snow. I had to put xfer case in Hi toget out but at one point the trans made a grinding noise similar to what I heard the other day. I later attributed it to the TC slipping due to low fluid from the leak. Once leak was repaired and trans refilled It didn't happen again. However last winter I was busting drifts on my road and had to rock the truck pretty dramatically to get out, it wasnt a few months later that the reverse issue cropped up. So all of that together has me thinking its the TC and maybe I can just replace that but I'm not sure how to diagnose that as the problem. Sure would be cheaper and easier than a rebuild.

Mark Kovalsky · Feb 1, 2015

It certainly isn't the torque converter. How would the converter not "engage" in reverse, but work in drive? The converter doesn't know if the trans is in drive or reverse.

Rocking the truck won't hurt the converter. But it is REALLY hard on the reverse and forward clutches.

The problem is inside the trans. My guess is that the reverse and now the forward clutches are failing.

Big Bore · Feb 1, 2015

Thanks Mark

high country · Feb 3, 2015

mine did the same thing. my clutch packs gave up. do you have a tugger in it? if not, it is money well spent.

Big Bore · Feb 3, 2015

Thanks high country,

According to the builder when I spoke to him a couple years ago it has a custom valve body. The receipt for the trans says it had a Vasco steel forward drum, Super Heavy Duty Converter (custom built according to the shop owner) with a billet front cover, heavy duty bearing and triple disc clutch. I'm hoping those components are reusable, need to research how to check. A log book entry says it also had an "updated center support" installed at that time but it is not on the receipt, I don't know what that center support entails. It also has the finned deep sump pan. An earlier receipt says it had OEM solenoid pack installed.

The trans has 90K on it since being rebuilt, most of those miles running steep passes, some heavy towing, plenty of hard throttle, 175cc single shots and 38R. I don't know if that's good or bad. I suspect had it not been for that fluid leak it would still be going. It has never been anywhere near hot according to the gauge even towing an extremely heavy load of wood over a 11K pass when it barely reached yellow on the gauge. Most of the time it was below green? It has a 6.0 cooler and inline filter.

Checking the dipstick it has black residue which I know is not good.

high country · Feb 3, 2015

$orry man. I don't know how your last build went, but the tugger is sweet to be able to drop into low and actually get some engine braking. Mine is drilled pretty agressively and shifts like a champ with php tunes.