Do larger tires require transmission fluid changed early?

[Jeep Junkie]

Stock my Jeep had 33" tires and 4.10 gears. Now I have 37" tires and 4.88 gears. Will such heavy tires wear out the transmission quicker? Same question about transfer case fluid.

Thank you!

 

[Jimmy_Russells]

Weren’t you going to change it every 25k anyway?

 

[Jeep Junkie]

Weren’t you going to change it every 25k anyway?

Yes but Jeep says 60k miles. If bigger tires don't affect the transmission fluid then I could do it at like 40k. It is not easy to service the 8 spd ZF transmission. It is not just the fluid, the filter is part of the drain pan and the whole thing needs to be replaced. I watched a Youtube video and it seemed like a big job to me

 

[wlk]

Yes but Jeep says 60k miles. If bigger tires don't affect the transmission fluid then I could do it at like 40k. It is not easy to service the 8 spd ZF transmission. It is not just the fluid, the filter is part of the drain pan and the whole thing needs to be replaced. I watched a Youtube video and it seemed like a big job to me

Can you siphon out a dipstick or did they get rid of it? Would be an easy service if so, takes me longer to get my vacuum pump, vacuum container and air compressor ready than it does to siphon out any vehicle i am servicing. Also, I would service any Chrysler tranny at Severe Service intervals no matter what. I have had 6 of them go bad over the years.

 

[thetricky]

Why not 3k changes?

 

[Infomercial]

Get good synthetic fluid and maybe an extra cooler. Your trans will work harder and get hotter.

 

[MuzzleFlash40]

Yes but Jeep says 60k miles. If bigger tires don't affect the transmission fluid then I could do it at like 40k. It is not easy to service the 8 spd ZF transmission. It is not just the fluid, the filter is part of the drain pan and the whole thing needs to be replaced. I watched a Youtube video and it seemed like a big job to me

I just had the trans serviced in my Wife’s 21 Grand Cherokee w/ 75k which is probably the same 8 speed in your wrangler. After watching the videos and not wanting to screw anything up. I just took it to the dealer. The Mopar fluid was just under $30 a quart and it took 6 quarts, the Mopar filter/pan was $250. They charged about $200 for labor. I’d just stick with the 60k. Since you added the larger gear to go with the tires, did your RPM’s even change that much?

 

[Lubener]

Stock my Jeep had 33" tires and 4.10 gears. Now I have 37" tires and 4.88 gears. Will such heavy tires wear out the transmission quicker? Same question about transfer case fluid.

Thank you!

That's a good one.

 

[OilStainedNapkin]

Yes but Jeep says 60k miles. If bigger tires don't affect the transmission fluid then I could do it at like 40k. It is not easy to service the 8 spd ZF transmission. It is not just the fluid, the filter is part of the drain pan and the whole thing needs to be replaced. I watched a Youtube video and it seemed like a big job to me

Weren’t you not gonna trust the jeep engineers anyway?

 

[4WD]

If your pan looks like this - the filter is not integrated …
Not sure what video you watched - but since they warm up very slowly - the job was easier than I expected (25K) …
I left the filter - cleaned pan/magnets & just did 5L of LG8 …

 

[supton]

Seems to me that the taller tire is offset by the deeper gearing, actually more so ofset. Then again, likely a heavier tire, so perhaps net sum zero during acceleration.

If this is a mall crawler then just stick to the manual. If this gets flogged off road often, then stock or not you’d be doing all fluids more often anyhow.

Got a trans temp gauge?

 

[4WD]

Can you siphon out a dipstick or did they get rid of it? Would be an easy service if so, takes me longer to get my vacuum pump, vacuum container and air compressor ready than it does to siphon out any vehicle i am servicing. Also, I would service any Chrysler tranny at Severe Service intervals no matter what. I have had 6 of them go bad over the years.

No dipstick - personally I place value on cleaning the magnets and pan on an early change …

 

[kschachn]

That's a good one.

No kidding.

I wonder how long this is going to last?

 

[BrendanC]

spill and fills are your friend on ANY transmission that will allow it. doesn’t PPE offer an aftermarket pan with a serviceable filter/drain plug?

 

[4WD]

spill and fills are your friend on ANY transmission that will allow it. doesn’t PPE offer an aftermarket pan with a serviceable filter/drain plug?

PPE is nice kit but unless things have changed - with the V6 - the cross over pipe will clash like on some other makes/models …
It runs very close to the pan - wrapped mine with header tape.
The 4 banger turbo does not have this issue …
I will have a B&M plug handy and decide …

 

[burbguy82]

If the mechanical advantage, has changed to a disadvantage, then the tranny will work harder. It is a math game with tire size gear ratio and tranny gear ratios per gear. This is something you should have accounted for before you had the work done.

Really, the tranny does the same work, but with a mechanical disadvantage, the engine will have to put more power through the tranny, and the result will be heat in the tranny.

 

[SC Maintenance]

PPE is nice kit but unless things have changed - with the V6 - the cross over pipe will clash like on some other makes/models …
It runs very close to the pan - wrapped mine with header tape.
The 4 banger turbo does not have this issue …
I will have a B&M plug handy and decide …

Is it a plastic pan or stamped steel? If its steel can you drill and add your own?

 

[SC Maintenance]

I will say this about off-road. I once pulled the rear diff plug on my Xterra and it came out chocolate milk (water ingested). Realize the breather is a hose with a filter in the rear tail-light 4 feet high, and as best I can tell the hose was intact (held air when I replaced it). It checked it often after, and the problem never persisted. .

My point - if you do actually off-road service is a whole different world. Its not about mileage or hours, you just need to check / change everything often. If you crawl the mall, then don't worry about it.

 

[4WD]

Is it a plastic pan or stamped steel? If its steel can you drill and add your own?

It’s steel - I did that on my 2010 & 2017 GM’s …

 

[supton]

I would think the real killer is when the torque convertor is unlocked, the heat buildup during take off from a stop. I don't know if many transmissions now run unlocked in the upper gears? My Tundra sure did--but it also had a decent OEM cooler too. That just leaves frequent shifting as a concern (maybe lock out upper gears if it starts getting shift happy in the hills).

Is this getting a bigger trans cooler? These days it seems transmissions do use a thermostat so as to ensure the trans stays good and warm; thus I'm not sure you can overcool it. Once it goes off road that extra cooler might be nice.

Don't see how though that this could be any tougher on the transfer case.

New gears? Aftermarket? Done by a local shop? I think I'd worry first about those. Not saying they can't be done right the first time, just that I'd be concerned there first (even though they are probably the cheapest part of the system). And most likely to be dunked under water, as already noted.