4Lo transmission slipping 1st gear (1 Viewer)

[cybrstar]

I noticed when I was on the rubicon last year that on 1 specific obstacle going uphill against a rock, right after the hairpin going uphill, the tranny was stalling out. Had the engine fully pined and it felt like it was in second gear. I ended up winching but never really figured it out. I was able to finish and tranny felt fine other than that moment. I already did the following, checked fluid levels, fluid condition, transmission selector, repositioning selector, did confirm transmission is shifting through all gears. Had suggestions that it could be transmission lockout solenoid, the t-case locking motor was in the open position, or even the torque converter maybe bad. Has anyone encountered this and what was your fix?

 

[BILT4ME]

I noticed when I was on the rubicon last year that on 1 specific obstacle going uphill against a rock, right after the hairpin going uphill, the tranny was stalling out. Had the engine fully pined and it felt like it was in second gear. I ended up winching but never really figured it out. I was able to finish and tranny felt fine other than that moment. I already did the following, checked fluid levels, fluid condition, transmission selector, repositioning selector, did confirm transmission is shifting through all gears. Had suggestions that it could be transmission lockout solenoid, the t-case locking motor was in the open position, or even the torque converter maybe bad. Has anyone encountered this and what was your fix?

Were you in low range on the transfer case?

 

[cybrstar]

Yes

 

[Dusten]

You verified it's not starting in second?

 

[cybrstar]

Yup, as mentioned above.

ToolsRUs……
you would have had the answer for this one. RIP.

 

[Dusten]

Yup, as mentioned above.

ToolsRUs……
you would have had the answer for this one. RIP.

You didn't say that it's not in second on low range. These transmissions use a second gear start.

 

[cybrstar]

Ohh tranny is a A442 94.

 

[use2bn83]

I’ve had this happen in Moab a couple times being super stuffed with plenty of traction. The truck just doesn’t have enough power to move. I’m sure just about anyone on 37’s-40’s can attest. I know when I built my 80 on 39’s I couldn’t get it to climb a small wall at the shop to flex it out without this happening.

I installed both high and low range gears from @cruiseroutfit and it has never happened again.

 

[cybrstar]

I’m on 37’s with 4.88’s. I don’t think gears in the transfer case will really do much as it basically does the same as installing 5.29’s. Had the gears in the T case before. Gears are a little louder and loose your top end for snow/sand/dessert runs.

 

[use2bn83]

I’m on 37’s with 4.88’s. I don’t think gears in the transfer case will really do much as it basically does the same as installing 5.29’s. Had the gears in the T case before. Gears are a little louder and loose your top end for snow/sand/dessert runs.

In this scenario it’s the low range gears that would be a huge help. The low high range gears help lower the low range a tiny bit as well.

You’re basically back to stock gearing with 4.88 and 37’s. Just not enough power there to push the rig/tire.

 

[baldilocks]

I’ve had this happen in Moab a couple times being super stuffed with plenty of traction. The truck just doesn’t have enough power to move. I’m sure just about anyone on 37’s-40’s can attest. I know when I built my 80 on 39’s I couldn’t get it to climb a small wall at the shop to flex it out without this happening.

I installed both high and low range gears from @cruiseroutfit and it has never happened again.

I don’t think I’d leave it right there. I crawl a few rocks myself for several years now in my 93 on 37’s/low range gears/4.88’s and have never experienced what the OP describes. The 80 really has no power deficiency at low speeds where torque is what’s relied on as in rock crawling. This is evident in the fact that the OP (having done much crawling in the past I’m sure) had also never experienced this problem.

I’ve been told by on lookers that my 80 seemed to pop up and over larger obstacles with what seemed like little effort despite the auto gear box. I’ve seen other vehicles with autos rev much higher as the converter slips and slips on the same obstacle. These are the people who comment on the 80’s non dramatic performance.

I’d be replacing my transmission fluid and inspecting the strainer if this happened with my rig.

A trans temp gauge is usually very boring to watch on these 80’s but I have one because anything can go wrong on any given day and knowing the trans temp can help us avert catastrophe.

 

[Dusten]

I don’t think I’d leave it right there. I crawl a few rocks myself for several years now in my 93 on 37’s/low range gears/4.88’s and have never experienced what the OP describes. The 80 really has no power deficiency at low speeds where torque is what’s relied on as in rock crawling. This is evident in the fact that the OP (having done much crawling in the past I’m sure) had also never experienced this problem.

I’ve been told by on lookers that my 80 seemed to pop up and over larger obstacles with what seemed like little effort despite the auto gear box. I’ve seen other vehicles with autos rev much higher as the converter slips and slips on the same obstacle. These are the people who comment on the 80’s non dramatic performance.

I’d be replacing my transmission fluid and inspecting the strainer if this happened with my rig.

A trans temp gauge is usually very boring to watch on these 80’s but I have one because anything can go wrong on any given day and knowing the trans temp can help us avert catastrophe.

It's boring... Unless you've cooked a trans. Or 3. I watch mine like a hawk now lol.

 

[use2bn83]

I don’t think I’d leave it right there. I crawl a few rocks myself for several years now in my 93 on 37’s/low range gears/4.88’s and have never experienced what the OP describes. The 80 really has no power deficiency at low speeds where torque is what’s relied on as in rock crawling. This is evident in the fact that the OP (having done much crawling in the past I’m sure) had also never experienced this problem.

I’ve been told by on lookers that my 80 seemed to pop up and over larger obstacles with what seemed like little effort despite the auto gear box. I’ve seen other vehicles with autos rev much higher as the converter slips and slips on the same obstacle. These are the people who comment on the 80’s non dramatic performance.

I’d be replacing my transmission fluid and inspecting the strainer if this happened with my rig.

A trans temp gauge is usually very boring to watch on these 80’s but I have one because anything can go wrong on any given day and knowing the trans temp can help us avert catastrophe.

OP should definitely vet out any potential mechanical issues. Just lending my experience, as I’ve had this happen a few times, but not since installing low range tcase gears.