Define no rollover noise

[84TD]

I have heard this statement many times on the forum after a SMF or ZF5 swap, "I use such and such fluid and I have no rollover noise"

Well I used lucas part synthetic ATF after my ZF swap and I have absolutely no rollover noise on the road. After the swap I was even wondering what folks were talking about its so quiet but if I am off road I hear alot of growling coming from the trans, if I am idling in 4 low through some soft ground its so loud I cannot even hear the engine running and it is super annoying.

Is there a better fluid I could be using for off road use? I will be off the road and on the beach for 4 days july 4th weekend and I really dont want to listen to the thing growling and howling the whole time.

 

[jrad235]

50w Synthetic. I used Royal Purple and it was great, except I had to slow down some of my shifts, and it was a bear to shift into certain gears when it was cold(Anything below 70, pretty much) Otherwise it was almost as quiet as the original flywheel when warm. When cold you couldn't hear a sound from the transmission.

 

[84TD]

I guess the definition I am looking for is for folks who have done the conversion is and dont have rollover noise under normal operating conditions is if you are idling in 4 low on a unpaved surface is that still the case?

 

[79jasper]

IMO, the noise you're hearing is NOT rollover noise.
Give er a lil throttle and the noise goes away I bet?

That's just "lugging" it. As I've heard, it's ******* the bearings.
Almost all trans I've been around can do it. Well except a sm465, but they're noisey as hell anyways.

My advice is don't do what you're doing, pick a lower gear and give it some throttle.

 

[84TD]

Thats right, if I get it to 1K the noise mostly goes away, if the truck lurches like going down a small bump and hitting the next it make the noise. Hard to describe, i guess it just sounds like muffled vibrating metal pieces. I assumed it was rollover noise because my T-19 never made a peep even idling up a 30 degree incline in 4 low and the ZF is blatantly loud idling up anything.

 

[79jasper]

It's the vibrations causing everything to rattle. Even stock dmf's do it.
It's just the way they work. I try to avoid it, but sometimes you can't.
I'm not sure that it causes any damage, but that's just what I've heard.

 

[84TD]

In my opinion I do not think anything that noisy is not causing some sort of advanced wearing but I could be wrong.

 

[89dieselbko]

Im with the above guy here, if it SOUNDS like its causing damage, or otherwise just bad, it IS causing some damage, and is bad!

also, guys with the SMF conversion normally pop the shifter off the top and add an extra quart, many threads talking about how
it helps to quiet it down, maybe give that a try? Also, zf5 + 4low + 1st gear, my bronco was quiet as can be, no noises, hell i could walk beside the thing while it idled down the road (live down a dirt road, and did this just for giggles, wife told me it wasnt possible lol) no bad noises, no nothing. but i had DMF, so maybe you are getting some rollover noise + luggin it 4low in maybe second or third gear?

 

[jrad235]

I know that when I had my DMF, I could stick the truck in first gear and crawl up a 9% grade at idle with minimal noise.

I know that when I had 50w in mine after the SMF change, I had a faint clatter at idle in neutral, but definitely acceptable compared to the hellacious growling that goes on with cold ATF currently.

If the weather is warm and your shifts are not hurried, just spend the money on the 50w Synthetic.

Honestly, I don't go crawling hardly ever, so I can't tell you for sure.

 

[cpdenton]

I will refer you to page 6 of this zf manual.

It has a troubleshooting section that deals with this exact noise below 1000 rpm. Calls it a lugging noise and says the fix is to not operate the transmission below 1000 rpm. (Love that fix btw). Also says it will not damage the transmission, although I do not like to hear it myself.

http://www.zf.com/media/media/docum...1/usa/lcv_3/S5-42_47__47M_Service_manual_.pdf

 

[79jasper]

So I was spot on. Cept the damage part.

 

[84TD]

Wow that is crazy. I am wondering if there is a better fluid I could use. Maybe ill try the straight 30w if I can find any without the detergent. From the noise it makes it sounds like a thicker fluid would help thing from bouncing around but it makes me nervous to put something in there not designed for the job. If a fluid makes it harder to shift it seems like that would cause accelerated wear to the syncros.

I think I heard about someone adding lucas oil stabilizer to it, might do that. Even the lucas "trans fix" stuff is way thicker than atf and its designed to blend with atf so maybe ill try that.

Also I think I will raise my idle up while I am off road, that should help.

 

[RLDSL]

Wow that is crazy. I am wondering if there is a better fluid I could use. Maybe ill try the straight 30w if I can find any without the detergent. From the noise it makes it sounds like a thicker fluid would help thing from bouncing around but it makes me nervous to put something in there not designed for the job. If a fluid makes it harder to shift it seems like that would cause accelerated wear to the syncros.

I think I heard about someone adding lucas oil stabilizer to it, might do that. Even the lucas "trans fix" stuff is way thicker than atf and its designed to blend with atf so maybe ill try that.

Also I think I will raise my idle up while I am off road, that should help.

You can use 30 wt synthetic ATF or even 50 wt synthetic ATF ( I personally run Amsoil 50 wt synthetic ATF, I used to run the 30 in both my zf and my Brownie but the rollover noise from my brownie was insane and I needed to take care of that so I did some chacking and found that the 50 wt atf crosses with lube speced by zf fro the box so it was a go, its worked great)
Do not use 50 wt synthetic oil unless it is NON DETERGENT( which is not an easy thing to find in a synthetic ) the detergents are not compatible with the box, you can run 30 wt NON detergent dino motor oil or non EP gear oil ( thats gear oil with no extreme pressure additives, again, doesnt play nice with the box will kick out of gear, these things rely on a certain amount of friction to function)
Do not overfill, just about Every tranny maker out there has a TSB on this somewhere, but its a no-no . you risk pressurized oil working past the input seal and trashing your clutch. Not worth it.
30 and 50 wt synthetic atf is generally available at places that service heavy trucks, it has become a standard fill for manual gearboxes on heavy trucks