MTFCA Forum

I know I'm stirring the hornets nest, but I have a legitimate oil question.

Lately I'm finding synthetic oil is as affordable and sometimes cheaper than conventional oil. So in my recent oil change I used 5w30 synthetic (4 QTs for only $8).

I seem to recall a passing comment that synthetic can cause transmission bands to not catch. Is there any validity or experience to this statement? My bands are fine, but once in a rare while it seems a band is slower to catch. I don't know if I'm playing mind games with myself or if I'm experiencing a legitimate issue due to synthetic oil.

Thanks, and here's hoping to no fights in this thread.
Chad

Slippage, reportedly due to synthetic oil, needs to be explained with the type of bands used, if bands were correctly adjusted, brand oil and weight, driving conditions and driver experience. There are just too many variables to eliminate preferences and rumor. just my 2 cents - oops forgot about inflation my 2 bits

Chad,,, no fight here,,,,, Been using Mobil One motorcycle 15W40 and wood band liners for 20 years with no problems,,, my oil choice was suggested by Fred Houston, past President of the MTFCA,and a noted Model T restorer, may he rest in Peace... Thanks Fred.

Bob J.

@TRDxB2, I have Kevlar bands and good drums. I believe they have been adjusted correctly. The issue can be on any gear and is very intermittent, normally no issues when driving. I'm experiencing this with my Hack and Touring, but not my Speedster (which I drove about 40 miles yesterday). I have been driving Model Ts for 12 years, but still learning.

I normally use 5w30 conventional, whatever brand is on sale. I have used higher weights. Perhaps this is an oil weight issue, especially in the heat of summer, and not a synthetic vs conventional oil issue.

FWIW, the synthetic oil was Gastrol. Chad

I have used regular & synthetic oils in my T's. I find no difference in band grip, one way or the other.

I have no specifics to quote, but my gut feeling is oil of 5w viscosity is too thin in a motor like a model T. I stick with 20w 40, which often comes up on special around $2/litre. It's a mineral oil, and is invariably cheaper than synthetics. With a climate similar to southern California, we have no need for thin winter weight oil.
I tried some 5w 30 in Henrietta, thinking it may help to flush out accumulated crud when I returned her to the road. On that oil, she ran no 1 rod bearing. Perhaps this was a coincidence. However, when fitting an exchange rod with the motor still in the car, I removed the pan inspection cover and the horse shoes in the pan. You would not believe the amount of gritty muck that was dammed up behind the horseshoes. I am glad the new oil had little time to turn this all loose.

Allan from down under.

Allan from down under

I think a lot oils do great, but when we are referring to a Model T, take into consideration that the engine is a splash system with no real filtration. A non detergent would be best and add a little zinc additive since it has not been in our production oils for about 5 years. Keeping the bad particles suspended in a splash system is in my opinion not really good. I use a straight 30 wt Rotella with about 4 oz of zinc additive. JMO!

All the Best,

Hank

Budreau wrote: ↑

Sun Jul 19, 2020 10:39 am

...I seem to recall a passing comment that synthetic can cause transmission bands to not catch. Is there any validity or experience to this statement? My bands are fine, but once in a rare while it seems a band is slower to catch. I don't know if I'm playing mind games with myself or if I'm experiencing a legitimate issue due to synthetic oil.
Thanks, and here's hoping to no fights in this thread.
Chad

Just trying to bring focus back to the original topic - its about the possibility of transmission bands slipping when using synthetic oil. A question I am also looking for an answer to. Two answers so far - no slippage when using wood or kevlar bands

I have Kev. Bands and always found them grabby or chatter, a quart of ATF stopped it . How ever when I converted to SynTec all chattering went away. First SynTec I used was Amsoil Z-Rod for classic cars and claimed to work well with wet clutch cars. Yep it was ok. But due to expense I have been using Walmart Full syntec 4 stork motorcycle oil also works well with wet clutches. I'm using 20/50 .

5w30, 15w40, 10w30 - all good information, but ultimately I'm curious if synthetic oil lubricates too well causing a occasional band slippage? I don't recall this issue with conventional. It's hard to quantify the occurrence, but this happens randomly on any gear in two of my three Model Ts. If I were to quantify the slippage, I'd say it happens once every 50 clutch/pedal engagements.

I'll probably give a half turn to tighten my bands, but before I do I was curious if this could possibly be an oil issue.

Thanks all!

Sorry Chad,

Never seen any ill effects. Long day in the sun yesterday!

Hank

Been using Amsoil10W-40 (high zinc) oil in my '26 Touring for 5 years now. Have kevlar bands properly adjusted. No issues with slippage at all.

Just my opinion... Starting out on a drive it seems like you have no problem with your bands applying as you adjusted... As the engine warms up, metal will expand a bit possibly causing the effect of loosening up your band contact on the drum...????